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Lewis123 Ver 1.0 Partialware Copyright 1986, Stone Age Software By Stephen Mehalek A covalent bond sketcher. Version 1.0 of Lewis123 is distributed as Partialware for your use. If you would like to upgrade to the fully functional version send $29.95 to Stone Age Software P.O. Box 1216 Amherst, NH 03031 PHONE (603) 673-8734 Compuserve PPN# 73277,2557 Dealer inquiries welcome Please distribute in any manner you see fit Version 1.0 of Lewis123 (Note! Any Version of Lewis123 higher than or equal to 2.0 may not be distributed as Partialware). In your distribution of the partialware version you must include the following files - Lewis123.PRG Lewis123.RSC Lewis123.DOC Partialware was created with the idea of letting the user test run a software package before purchasing it. 90% of the functionality of Lewis123 is retained in this version. It is quite possible that the Partialware version of Lewis123 may be sufficient for your needs. If your needs are met by the Partialware version, we are still very interested in your comments on the product i.e. Bugs, features you want, and omissions in the documentation. ---------------------------------------------------------------------- Trademark Acknowledgements ATARI, 520ST,ST, and TOS are all registered trademarks of Atari Corp. GEM is a registered trademark of Digital Research Inc. Gemini-10x is a registered trademark of Star Micronics Inc. Degas is a registered trademark of Batteries Included. Epson is a registered trademark of Epson America Inc. ---------------------------------------------------------------------- Limitations of warranty and liability. Stone Age Software Inc., or any person or distributor distributing this product, makes No Warranty, Expressed or Implied, with respect to this program, the documentation, and any other related items, their quality, performance, merchantability, or fitness for any particular use. It is solely the users responsibility to determine their suitability for any particular purpose. Stone Age Software Inc. will in no event be held liable for direct, indirect or incidental damages resulting from any defect or omission in this documentation, the program, or other related items and processes, including but not limited to any loss of business or anticipatory profit, interruption of services or other damages resulting from the use of this product. This statement of limited liability is in lieu of all other statements of limited liability and all other warranties, implieded or expressed. This statement of limited liability includes warranties of merchantability and fitness for a particular use or purpose. Stone Age Software Inc. neither assumes nor authorizes any other person or distributor to assume for Stone Age Software Inc. any other Warranty of liability in connection with the sale of this product. The documentation and programs contained in the accompanying disks described herein are copyrighted and contain information proprietary to Stone Age Software Inc. Versions of Lewis123 higher than or equal to 2.0 may not be copied or used for any other purpose than the backup of Lewis123 by the original purchaser. --------------------------------------------------------------------- Upgrade policy Upgrades of Lewis123 maybe purchased from Stone Age Software Inc. for the flat fee of $10 at anytime. This applies only to users who possess a valid copy of a Lewis123 system disk, and to those users who possess versions of Lewis123 higher than or equal to 2.0. Versions of Lewis123 lower than 2.0 are provided as Partialware and maybe be distributed freely. Versions equal to or higher than 2.0 maynot be copied or reproduce in anyway except for the purposes of backup by the user. --------------------------------------------------------------------- Table of Contents 1.0 Overview of Lewis123, System requirements, and Product Interfaces 1.1 Overview 1.2 System requirements 1.3 Interface to Other Products 2.0 Running Lewis123 3.0 User Interface Description 3.1 Overall Layout 3.2 Menu Structure and Operation 3.2.1 Desk 3.2.1.1 Read This! 3.2.2.2 Accessory 1 Through Accessory 6 3.2.2 File 3.2.2.1 Open... 3.2.2.2 Save 3.2.2.3 Saveas... 3.2.2.4 Save To Degas Pic... 3.2.2.5 Save To Metafile... 3.2.2.6 Print... 3.2.2.7 New Structure 3.2.2.8 Delete File... 3.2.2.9 Quit 3.2.3 Options 3.2.3.1 Ionize an Element... 3.2.3.2 Calculate Formal Charge 3.2.3.3 Statistics on Complex 3.2.3.4 Info State on 3.2.3.5 Thickened Lines 3.2.4 Group IA Elements 3.2.5 Group IIA Elements 3.2.6 Group IIIA Elements 3.2.7 Group IVA Elements 3.2.8 Group VA Elements 3.2.9 Group VIA Elements 3.2.10 Group VIIA Elements 3.2.11 Group Zero Elements 3.3 Mouse Operations 3.3.1 Single Click 3.3.2 Double Click 3.3.3 Drag 3.3.4 Drag to the Trash Can 3.4 The Spacebar 4.0 Tutorial on Drawing a Benzene Molecule 4.1 Basic Steps to Drawing a Complex With Lewis123 4.2 Example, Benzene 4.3 Steps to Depicting a Classic Lewis Structures 5.0 Problems and Possible Solutions 5.1 Lewis123 in not Starting. 5.2 After a Bond the Wrong Electrons Disappear. 5.3 When I Unbond the Wrong Lines Disappear. 5.4 When I Unbond the Electron Configuration Looks Different. 5.5 How Can I Orient the Valence Electrons Differently. 5.6 How Can I Choose What Spot Lewis123 Draws Its Lines to. 5.7 I Moved Everything Around on the Screen, and Its a Mess. 5.8 What Can I Do About Getting Rid of the Trash Can. 5.9 The Unshared and Bond Count Are Huge 65,000 or greater. 6.0 Limitations of Lewis123 6.1 Maximum Number of Entries 6.2 Desk Accessories 6.3 Memory Consumption 7.0 File Save Formats 7.1 Degas Save Format 7.2 Metafile Save Format 7.3 Lewis123 Save Format 8.0 Printer Support 8.1 Printer Drivers Available for Lewis123 8.2 Writing a Printer Driver for Lewis123 9.0 Product News From Stone Age Software ----------------------------------------------------------------------- Manual for Lewis123 1.0 Overview of Lewis123 and System requirements 1.1 Overview Lewis123 is the first spreadsheet for chemistry students, chemistry professors, chemists in industry, organic chemist, and any person who might need to deal with covalent bonds. Lewis123 with its interactive bond sketching environment can greatly enhance a Chemistry students ability to grasp the concept of covalent bonding. Lewis123 can also dramatically reduce the time necessary for an organic chemist to draw the multitude of organic structures that he may have to depict. For those users who feel confident in their ability to use GEM programs (or for hackers who never bother to read the manual) we suggest they read section 1.2 on system requirements and skip to Section 4.0 on the Benzene tutorial. Section 4.0 will skip all the gory details of the structure and function of Lewis123, and take you right into a short tutorial on how to draw a molecule. After completing the tutor you should be fluent on how to use 90% of Lewis123. 1.2 System requirements Lewis123 has the following system requirements: Monochrome monitor At least 105K bytes of free RAM and Tos in ROM 1.3 Interface to Other Products Lewis123 will save graphic output in the following formats Degas PI3 file format. This is a Monochrome format as defined in the Degas manual. Metafile format. This is the graphics standard format that all GEM based programs should use to transfer graphics data to any program! At present we are still waiting for Atari to release GDOS. When this occurs we implement the metafile save option. Note. Lewis123 files themselves are not graphics pictures in themselves, so graphics programs may not use them as graphic images of a Lewis123 complex. Lewis123 files are a collection of non- standard GEM objects that in this program correspond to the elements that make up a Lewis123 complex. Lewis123 will support any standard Degas printer driver. Included with the fully functional version is a Epson printer driver from Tom Hudson and Batteries included. This driver is provided as is, and is not being sold by Stone Age Software Inc. The driver is being distributed with the permission of Batteries Included. We fully support the Degas printer driver format, and beleive it should be the industry standard until GDOS is released by Atari. 2.0 Running Lewis123 Lewis123 is not a copy write protected program so no special measures, like having a system disk in Drive A need be implemented to run it. Please don't abuse this! Lewis123 requires the following files to execute properly. Lewis123.prg Lewis123.rsc Double click on the Lewis123.prg file and the program will display a menu bar, white background, and a trash can in the lower right hand corner, provide the program successfully started. If the program crashes goto section 5.0 on Problem Solving. 3.0 User Interface Description 3.1 Overall Layout Lewis123 is a fully GEM based program. It uses the standard file selection menu, a non-movable trash can, the mouse, and a menu based interface for element selection. The menu bar itself has 11 titles running across the top of the Lewis123 program screen as follows ---------------------------------------------------------------- | Desk File Options IA IIA IIIA IVA VA VIA VIIA Zero | ---------------------------------------------------------------- Sections 2.2 that follows describes each Menu title and all items under a title in detail. The mouse portion of the GEM interface for Lewis123 uses only the left button. This is the same button that you would use for clicking on items on the desktop. Section 2.3 describes the significance of a single click, double click, and highlighting with the mouse. 3.2 Menu structure and Operation 3.2.1 Desk The very first title in the far left corner of the Lewis123 screen is the Desk. When a user places the mouse over this area a menu that looks like this should pop down. ------------------ | Desk ------------------ | Read This! | |----------------| | (Accessory 1) | |----------------| | (Accessory 2) | |----------------| | (Accessory 3) | |----------------| | (Accessory 4) | |----------------| | (Accessory 5) | |----------------| | (Accessory 6) | ------------------ This area contains the credits dialog box for Lewis123 in the "Read This!" item. "(Accessory 1)" through "(Accessory 6)" are specific to your GEM environment. For example you might have chosen to install Desk accessory 1 , a calculator, and a clock in these areas. 3.2.1.1 Read This! Selecting this item reveals a dialog box containing the credits for Lewis123. If you select this while you are on the Desktop you will see a credit dialog for Atari. This dialog box has no effect on the function of the program. 3.2.1.2 Accessory 1 Through Accessory 6 These items contain user specific accessories that are optional i.e. clocks, calculators, and other items. 3.2.2 File Selection of the "File" title should bring up the following menu items ----------------------- File ------------------------ | Open... | |----------------------| | Save | | Save as... | | Save to Degas Pic...| | Save to Metafile... | |----------------------| | Print File... | |----------------------| | New Structure | | Delete File... | |----------------------| | Quit | ------------------------ This menu bar should contain all the file manipulation routines available to Lewis123. 3.2.2.1 Open This menu item is responsible for loading into memory Lewis123 files. Clicking on this option will bring up the standard menu selection box. Unlike, other programs Lewis123 does not attach a file extension to the filename. A good example of this is Degas files. A file name such as "mountain.PI3" has an extension of PI3 to donate to the program that it is a high resolution picture. Similarly, an extension of PI2 and PI1 denote a medium and low resolution file in that order. Since organic complexs tend to have long names it was thought the extra three characters could better be used in naming a file rather than as group extension identifier. If you don't use an extension we suggest using ".123", of course. Since the Atari manual doesn't describe the standard file selection box, here's a shot at a terse overview. You may use the mouse to do your file selection by double clicking on the filename, and use the vertical sliders to move through the files. The closer button in this box updates the file display i.e. use this button if you've changed diskettes and want to see the new list of files. The selector at the start of the program points to drive B:, if you need to change this the quickest way is to move the editing bar up to the path line, hit the ESC key, type "A:", and hit the closer button for an update of the files. Lewis123 will automatically retain the previous file name from a file select provided you previously used this option. This will occur even when using the delete file version, even though the file has been deleted (Aids in using the save as option). 3.2.2.2 Save This option will only appear if you previously loaded a file, using the "Open" option, into Lewis123. It should appear as low intensity text the rest of the time. Use this item if you load in a file and don't wish to go through the file selection box provided by the "Save as" file selector. The file will be saved under the name that was used to load it in. 3.2.2.3 Save as This is the only save function that may be used when you haven't used the "Open" item to select a file previously. Clicking on this item will provide you with a standard file selection dialog box to aid in the naming of your file. 3.2.2.4 Save to Degas Pic (Note! This function is only available on the fully functional version of Lewis123). This menu item will only become active after you have loaded in a Lewis123 file. If you click on this option after you have loaded a Lewis123 file you see the familar file selection menu. Select a file name and disk drive that you want to save the file to. The disk drive should not be write protected, and 32034 bytes should be free on it. After the the file has been correctly saved your complex will be redrawn on the screen with the garbage can. The reason we make you use the load option before you can use the save to Degas option, is to incourage you to save your work. 3.2.2.4 Save to Metafile This option will not be available until Atari releases GDOS. 3.2.2.5 Print File (Note! This function is only available on the fully functional version of Lewis123). You may use any Degas printer driver to preform printer dumps with Lewis123. We have included an Epson printer driver for use with your programs. Many thanks to Tom Hudson for taking a step forward and proposing a printer driver standard till GDOS arrives. We at Stone Age Software Inc. fully suppot the Degas printer standard, and encourage other software devlopers to do so also. The Epson printer driver included here is distributed as is, and is the property of Tom Hudson and Batteries included. The program driver is not being sold as part of Lewis123, but is being distributed for your use. If you have need of other printer drivers you may fine them in DL4 of the Atari 16 bit section of Compuserve SIG*Atari. Local users general have copies of various Degas printer drivers available for your use also. The sequence for using the "PRINT" option is as follows. The first time you select this option you will be prompted with the GEM file selction box. You should select the printer driver that you want installed to drive your particular printer. The printer driver that you do select will be installed for the remainder of your session with Lewis123. If you are using the Epson driver included on the Lewis123 system disk select the "Epson.prt" file. Otherwise select a printer driver that conforms to the Degas standard. After you have selected a printer driver the screen will be cleared and the complex will be printed without the menu bar and the trashcan. To stop the print out press the "UNDO" key. On successive selections of the "PRINT" option you will not be asked to select a printer driver. If you installed the wrong printer driver save your work and exit Lewis123. When GDOS is released we plan to provide printer dumps via the GDOS drivers. 3.2.2.6 New Structure This item will erase the current structure that is loaded into memory. If a structure is currently in memory an alert box will appear asking about the wiseness of utilizing this option. 3.2.2.7 Quit This item terminates the Lewis123 program. As is the case in "New Structure" you will be prompted if a complex is in memory, else the program will terminate minus the dialog box. 3.2.3 Options ---------------------------- Options ---------------------------- | Ionize an Element... | |--------------------------| | Calculate Formal Charge | | Statistics on Complex | |--------------------------| | Info State on | |--------------------------| | Thickened Lines | ---------------------------- The "Options" title contains a group of utilities to aid in constructing your Lewis complex, as well as an option to change the appearance of the graphics output. 3.2.3.1 Ionize an Element This option allows the user to add or subtract electrons from a given element. Choosing an element to ionize, requires that one be selected by clicking on the element first with the mouse. The user should see an elements name displayed in reverse video on the draw board if it has been selected for ionization. Reverse video is also the method used to draw bonds, and select elements for calculation of the formal charge. The effects of clicking and double clicking are discussed in more detail in section 3.3 on mouse operations. The basic point to remember here is that you should first have selected an element for ionization by highlighting it in reverse video. If no element was selected in reverse video the ionization dialog box will ignore the results of the dialog. The basic ionization dialog box is a collection of radio buttons and two exit buttons. Radio buttons in GEM are very similar to push buttons on a car radio, hence the term has been applied to them. If you look at the top two selections for the sign buttons, you have a choice of selecting subtraction or addition of electrons. The thing that makes radio buttons special is that you can never select more than one option at a time. In the case above, you will never be able to select the subtract electrons option without having the add electrons option deselected. One important thing about addition and subtraction of electrons is that an element may never have more than zero or eight electrons displayed at once without generating an alert box. In the case of zero you may never subtract more electrons than is displayed on the drawing board at any time for an element. In the case of eight electrons conversely, you may never display more than eight electrons around an element at one time. A very important point comes forth out of this discussion of the maximum and minimum electrons displayable by Lewis123. Lewis123 cannot judge the relative merits of a bonds existence or non-existence. Lewis123 is purely a sketch tool with a set tools designed to aid you in judging the merits or demerits of a bond. In no way shape or form can this program know whether or not your complex should exist. Conditions maybe such that your complex could not possible exist i.e. low pressure, high pressure, low temperature, high temperature, etc. You have to be the judge as to the relative merits of your bonds. Lewis123 does however provide you with information, warnings wherever possible, and a formal charge calculator to help you make these calculations. 3.2.3.2 Calculate Formal Charge The formal charge calculator, allows the user to calculate the formal charge of any element on the drawing board. To do this you must again select an element by clicking on it to get reverse video. Again, section 3.3 on mouse interfaces has a better discussion of the highlight and dehighlight commands. The formal charge calculator will display a dialog box with a number representing the formal charge of an element. Please keep in mind, that just because the formal charges look good doesn't guarantee that the bonds you have drawn are correct. This function is provided to aid in the tedium of computing formal charges of a complex. Its inclusion in this program doesn't guarantee anything. You as the Chemist or Student must make the judgement calls as to the soundness of complexes. 3.2.3.3 Statistics on Complex This item provides the user with two types of information on a complex. First, a count is displayed of all elements user to build a complex. Second, the number of bonds and unshared electrons to complete a complex is displayed. The element count is a simple tally of all elements on the drawing board. This means that if you have drawn a complex and have strayt elements on the drawing board you will have to drag them into the trash to get and accurate count. The number of bonds needed to complete a Lewis structure and the number of unshared electrons in a Lewis structure are based on the following calculations: Step 1. All the valence electrons were counted for each element on the drawing board. 2. We determined the number of electrons that would be needed to give 8 electrons to all elements excepte Hydrogen. Hydrogen was counted as 2. 3. The number obtained in step 2 minus the number in step 1 was calculated. That number yielded the number of bonding electrons. 4. Half of the number in step 3. Yields the number of bonds in a complex. This is the first number that we display i.e. the number of bonds needed to complete a Lewis structure. 5. We obtained the number of unshared electrons by subtracting step 3 from step 1. The above calculations will not work when bonds have already been drawn between elements on the drawing board. This menas that you must first place all your elements on the screen, and ionize them if appropriate to get accurate results. The count for the number of bonds and the number of unshared electrons may not be accurate even if you implemented the "Statistics" option correctly. To understand why it maynot be accurate you need to understand what principles the calculations that were stated above are based on. When Gilbert Lewis came up with his theory of covalent bonding, he based it on the principle of the octet. Gilbert theorized that all atoms, with the exception of Hydrogen, would try to form an octet with there valence electrons. The idea of the octet was taken from the noble gases which are very stable and do not readily react (Chemically stable, not necessarily atomically stable). This theory of bonding was a tremendous step forwared and went a long way to describing why/how elements make covalent bonds. Unfortunately the theory proposed by Gilbert is not always accurate. Many exceptions can be found to the octet rule. Especially cases where the valence electrons exceed and octet. Hence, the number of bonds predicted by this method maynot be correct all the time. After it became apparent that the octet rule was not adequate, a new theory based on the electrons pair was developed. The electron pair theory based itself on the fact that the electrons pairing together were the most relevant factor in bonding. Lewis123 was also developed with the electron pair as the most significant factor in covalent bonding. Lewis123 looks at the elements you are trying to bond, and searches first for unpaired and then for paired electrons to form a bond with. Since many text books treat classic Lewis structures extensively. We have preformed the basic caculations involved in drawing a Lewis structure for you. As we have pointed out the results of these calculations maynot always be correct. In order to reset the screen after using this function depress the space bar for a screen refresh. The statistics function just erases the screen and writes text to the drawing board. It doesn't place the program in another mode. This means that you may select elements for use in your complex and they will be displayed right in the midst of the statistics text. 3.2.3.4 Info State on Check marking the info state will provide online information about an element. The best way to understand this option is to turn it on and select a few elements from the various groups. A few clicks with the mouse quickly reveals a host of useful information on each element, that should keep you from having to reference your chemistry books all the time. Keep in mind that you must uncheck the "Info State on" menu item to get the elements placed on the drawing board again. 3.2.3.5 Thickened Lines All lines in Lewis123 are initially draw one pixel wide. If you find that one pixel wide lines are hard to see, or that you dislike the appearance. Check mark the thickened lines option. The screen will be redrawn, and all lines from that point on will be three pixels wide. Remember that you can save the drawing board to Degas and Metafiles when the thickened line option has been selected. 3.2.4 Group IA Elements When you drag the mouse over the menu titles "IA" through "0" you probably noticed that a list of elements pops down for each menu title. The menu titles, "IA" through "0", and the menu item lists for each menu title, correspond to the Periodic Chart groups. Most of you are probably already wondering what happened to the group B elements, the lanthanides, and the actinides. Bond representations of those elements not in group A would most likely not be done using the covalent bond approach. Most non group A bonds are crystalline structures and wouldn't be depicted using a covalent bond approach, but rather an Ionic or Metallic bond approach. Of course there are numerous exceptions to this rule of thumb, but Lewis123 is geared more towards sketching organic complexs than the whole gamut of structures. See section 3.3.1 for more information. To select elements for bonding click on the particular menu item and the element will appear on the bottom portion of the work sheet. Make sure you are not in the info state mode or all you will receive are dialog boxes with information on the element you are trying to select. As you click on elements they will be placed on the bottom of the drawing board in a right to left fashion. If you fill up the bottom row with element selections, the elements will be placed in the next available row. After selecting a few elements you are ready to proceed with actually drawing a few bonds. To draw bonds and drag elements around the screen read the section on mouse operations. For those of you who wish to proceed from here the basic operations are: Click with hold over an element: Will drag it two a new location on the screen. Click over an element: Selects it for bonding, ionization, or formal charge calculation. The elements name will be displayed in reverse video. Click on another element and you have a bond. Double clicking: Selects an element for unbonding. The elements name will be displayed in low intensity text. Selecting another element to unbond, will make this function work. Group IA is composed of the following elements: Hydrogen Lithium Sodium Potassium Rubidium Cesium Francium 3.2.5 Group IIA Elements Group IIA is composed of the following elements: Beryllium Magnesium Calcium Strontium Barium Radium 3.2.6 Group IIIA Elements Group IIIA is composed of the following elements: Boron Aluminum Gallium Indium Thallium 3.2.7 Group IVA Elements Group IVA is composed of the following elements: Carbon Silicon Germanium Tin Lead 3.2.8 Group VA Elements Group VA is composed of the following elements: Nitrogen Phosphorus Arsenic Antimony Bismuth 3.2.9 Group VIA Elements Group VIA is composed of the following elements: Oxygen Sulfur Selenium Tellurium Polonium 3.2.10 Group VIIA Elements Group IVA is composed of the following elements: Flourine Chlorine Bromine Iodine Astatine 3.2.11 Group Zero Elements Group IVA is composed of the following elements: Helium Neon Argon Krypton Xenon Radon 3.3 Mouse operations The mouse is the basic means by which elements are bonded, unbond (bonding using the single click, unbonding uses the double click), and moved on the screen. It is also used to select which elements you want to ionize, or which elements you want to calculate the formal charge of. 3.3.1 Single click A single click when the mouse pointer is over an element on the drawing board will highlight the element name in reverse video. After selecting an element you may bond it with another element by clicking over the element in question, or may select the ionization or formal charge menu item from the "Options" menu title. To deselect the element either click the mouse on top of the selected element or in a blank region of the screen. When you use the bond option, by highlighting and then highlighting another element, you may encounter some warnings and errors. The first and second period elements generally support one to four bonds. This would mean in the case of Hydrogen or Helium, you will be presented with a dialog box asking whether or not you want to proceed with the bond. The second error you may receive, is an error stating that the elements you are trying to bond, do not have the proper electron configuration to produce a bond. To understand this error you must first understand a little behind the logic that Lewis123 uses when it tries to make a bond. Since the electron pair is generally everything in a covalent organic bond, Lewis123 will look on the source and destination element for electrons to pair. Lewis123 looks for single electrons on the target and the source element to pair together. Hydrogen is a perfect example of an element with unpaired electrons floating around it. If Lewis123 doesn't find any single electrons around both the source and destination, it looks for a pair of electrons on the source or target. If it locates a pair of electrons, the next chore for Lewis123 is to find out if the valence structure of the target or source element can support an additional bond. If none of these conditions are found an electron bonding error will occur. In those cases where the user actually wanted to draw a bond, but received an error, there is a way to trick Lewis123 into making the bond. If the error resulted from a lack of electrons, simply add a some electrons to one of the elements. After adding some electrons make sure that the valence electrons configuration is correct. If there are extra electrons subtract out the excess by using the ionization feature of Lewis123. If the bonding error resulted from the valence electron configuration being full, you should subtract out electrons then make any corrections to the valence structure by adding electrons. It may seem strange to add and subtract electrons when the element will never have this configuration in real life, but this technique should allow you to circumvent the improper electron configuration problem. Since Lewis123 looks for electron pairs when making a bond, it behoves us to mention that Lewis123 will not always pick correctly. In the case of most organic molecules Lewis123 safely draws organic structures correctly 99% of the time. In the case of true Lewis structures, those based on the octet rule, strange results may result from drawing bonds. The solution to this problem is to carefully examine the results. If the results are not in keeping with your knowledge of the complexs structure, change the structure. You will have to use the ionization feature to fix the electron configurations if they are improper. If the element in question is a true Lewis structure use the "Statistics" option to calculate the number of bonds and unshared electrons that are necessary to complete your structure. 3.3.2 Double click If you double click over an element you will highlight that element for unbonding. The elements name should appear in low intensity text. Selection of another element will unbond one of the bonds between those elements. You should be aware that Lewis123 doesn't keep track of the order in which lines where drawn between elements. This means that the last line you drew is not necessarily the line that is removed on the screen. If you want a particular line undone, you may have to remove several lines. Sometimes it is more convenient to just throw the element in question away. Most of the time Lewis123 does a pretty good job of removing lines in palatable way. You should also be advised that you can have an element selected for unbonding and selected for bonding at the same time. This option is very handy when you have moved one element relative to another and the bond line looks poor. Just unbond and redraw the bond to fix the appearance. 3.3.3 Drag If you click and hold the mouse while over an element you should be able to drag the element almost anywhere on the drawing board. Lewis123 will not let you drag one element over another though. You may also drag elements that have been bonded. The bonds themselves will not be reorganized as you drag the element, but the lines will be repositioned at the end of the drag. Taking this into to account, you can have your bond lines cut through areas of the screen you wouldn't want them to. If this occurs drag the element elsewhere and hit the spacebar to redraw the screen, or unbond the element and try to redraw the bond for a better appearance. 3.3.4 Drag to the Trash Can If you drag an element to the trash can it is deleted and all bonds are undone. 3.4 The spacebar The spacebar will redraw the screen whenever you depress it. The spacebar is also required to be used after you get statistics on a particular complex. 4.0 Tutorial on Drawing a Benzene Molecule This tutorial will describe the basic steps you must take in using Lewis123 to depict an organic structure, in this case a benzene ring. 4.1 Basic Steps to Drawing a Complex With Lewis123 If your going to master drawing complexes with Lewis123, you are going to need to master four things: Element Selection - This is done by clicking on elements from one of the seven menu titles. The titles correspond to the Group numbers on a periodic chart. The items in each menu title correspond to the elements themselves in that group. To select one click on the element and it will appear at the bottom of the screen. You may drag elements on the screen to arrange them. Bonding - To bond two elements together select the first by single clicking when the mouse pointer is over top of the element. The element should now be displayed in reverse video. Then click the mouse when the pointer is over another element that you wish to bond to. Unbonding - To unbond elements that have been bonded, you may drag them to the trash, or double click on one element and select another element to unbond and then double click. Ionization - To ionize an element use the same technique that you would use to bond to two elements together. Only this time, select the ionization option from the "Options" menu when an element is highlighted. 4.2 Example, Benzene Benzene is made up of six Hydrogen atoms and six Carbon atoms bound together in the shape of a pentagon. Benzene is represented by a resonance structure in real life, in this tutorial we will only depict one variation. First, select the six Carbon and the six Hydrogen atoms by clicking on the menu items in Group IA and Group VIA that correspond to the elements. Arrange the six Carbon atoms in the shape of a stop sign. Position the remaining Hydrogen atoms around the stop sign or Carbon atoms, one for each Carbon atom as depicted below: H H C C H C C H C C H H If you select the "Statistics" options from the "Options" menu title. You will see at the bottom of the statistics a count of the total number of bonds and the total number of unshared electrons in the Benzene complex. Reading these off we see that we need 15 bonds to complete the structure, and no electrons will be left over. Connect the Carbon atoms together by drawing a single bond and then a double bond in an alternating pattern. Now connect one Hydrogen atom to each of the Carbon atoms. You have now correctly depicted a Benzene ring. Use the open function to compare your structure with that of the Benzene molecule that we have drawn (Load the BENZENE file). Be careful when using the "Open" to load the Benzene example. Your work will be erased if you don't save it first. It took us two minutes on average to depict the benzene structure. 4.3 Steps to Depicting a Classic Lewis Structure A classic Lewis structure is by our definition a molecule or complex that is based in part or in whole on the concept of the attainment of the noble-gas configurations on the part of atoms in covalent molecules. If you wish to depict classic Lewis structures you should use the following steps: 1. Place all the elements that make up your complex on the drawing board. Then ionize any elements that should be ionized. Now select the "Statistics" option from the "Options" title on the menu bar. Selecting the "Statistics" option will provide you with the number you need for step's 2 and 3. 2. You must indicate the covalent bonds between each of the elements by using the single click option to draw bonds. You are also responsible for arranging the elements on the drawing board with correct placement. Draw at least one bond between all the atoms first. Then distribute the remaining bonds. 3. Evaluate the formal charge of each atom, and inspect your work for errors i.e do the valence electrons total up to the number of unshared electrons in step one. Remember, Lewis123 looks for the electron pair on atoms when it tries to draw a bond. If the electron configuration is incorrect use the ionization feature of Lewis123 to correct it. 5.0 Problems and Possible Solutions 5.1 Lewis123 in not Starting. Check that the resource file Lewis123.rsc is with the program. You will receive a waring if this is the case. Make sure that you have TOS in ROM. If this is not the case upgrade you system. Lewis123 will run somewhat without TOS in ROM, but the "FILE" options crash the system. If you are doing this be careful and use a copy of LEWIS123 on a separate disk. A crash in the "FILE" options could damage your diskette. We haven't had this happen, but we don't like the idea of the program crashing when it is doing file IO. This information is supplied for those people who want to look at the program with TOS in RAM. USE AT YOUR OWN DISCRETION IF THIS IS THE CASE. 5.2 After a Bond the Wrong Electrons Disappear. Lewis123 looks for the electron pair on elements it is trying to bond. If you are trying to draw a classic Lewis structure as we have defined in section 4.0 you may have this problem. Try using the ionization option of Lewis123 to correct the electron configuration. See section 3.3.1 for a full explanation of what is going on here. 5.3 When I Unbond the Wrong Lines Disappear. Lewis123 does not unbond elements in the order that the bonds lines where drawn. This means at times Lewis123 will take away bond lines that leave a visually unpleasing look. Drag the element to the trash for a quick fix. 5.4 When I Unbond the Electron Configuration Looks Different. Lewis123 will always give back correct number electrons it took from an element in a bond. If the element has been bonded elsewhere the electrons may be given back as single electrons or pairs. This may at first seem confusing, but look at the bond again and you'll see that it has the same number of electrons, but they maybe arranged differently. 5.5 How Can I Orient the Valence Electrons Differently. You can't. Lewis123 uses its own algorithms to determine where it is going to place valence electrons around elements. You may try stripping all the electrons from an element using the Ionization feature, and then adding all of them back using the Ionization feature. 5.6 How Can I Choose What Spot Lewis123 Draws Its Lines to. You can't. Lewis123 uses its own algorithm to determine where it is going to draw the next line. If a line was draw to a spot on an element that was not particularly visually pleasing, unbond the element and try from a slightly different point on the drawing plane. 5.7 I Moved Everything Around on the Screen, and Its a Mess. Depressing the space bar and it will redraw the screen any time this occurs. As you move elements around the bonds do no resituate themselves on the elements. This means that it may be necessary to unbond and redraw your bond if the move causes visual problems. 5.8 What Can I Do About Getting Rid of the Trash Can. The trash can is a fixed object that cannot be removed from the drawing board. The trash can will disappear when you go to print out the complex or save it to a Degas or Metafile. 5.9 The Unshared and Bond Count Are Huge 65000 or greater. The numbers you are seeing are Lewis123's attempt to display a negative number. Two things may cause this. First, for the calculations to work all the elements must be unbonded on the drawing board. You can't have any stray elements on the drawing board either. The second reason, as we tried to explain in section 3.2.3.3 on the "Statistics" option the concept of bonds based on octets maynot be appriopriate for you complex. The elements that you are trying to depict may exist ionization levels that don't make sense when plugged into the caculations for classic Lewis structures. 6.0 Limitations of Lewis123 6.1 Maximum Number of Entries 400 elements may be placed on the screen at once. 6.2 Desk Accessories Lewis123 requires no desk accessories. Lewis123 is a fully GEM based program, hence it will operate with other programs or accessories designed to run in a GEM based environment. Some programs written in older versions of FORTH that were not relocatable could cause problems. In general be suspicious of programs that are generated as non-relocatable code. 6.3 Memory Consumption Lewis123 require 105K bytes of free RAM. 7.0 File Save Formats 7.1 Degas Save Format (Note! This function is only available on the fully functional version of Lewis123). Saves the drawing board to a Degas PI3 file. 7.2 Metafile Save Format Saves the drawing board to a Metafile format. This option will only be available when Atari releases GDOS for use. 7.3 Lewis123 Save Format Lewis123 files are a collection of non-standard objects. Lewis123 files will not work with other graphics programs. 8.0 Printer Support 8.1 Printer Drivers Available for Lewis123 Lewis123 will support any standard Degas printer driver available. 8.2 Writing a Printer Driver for Lewis123 Reference the Degas manual for details on this standard. 9.0 Product News From Stone Age Software Due out August, 1986. For software developers, publisher of magazines on diskettes, and anybody who needs documentation on diskette we have the solution. Doc on a Diskette is program that formats your text files for easier viewing, allows users instant access to a table of contents or index, allows users to move freely in a document, has fully GEM based user interface, and allows graphics pictures to be interspersed throughout the document (Requires Degas). Finally a standard for the industry, online documentation that works. One purchase, buys the rights to use of Doc on a Diskette for one of your products. No royalties. A full function scientific calculator for both monochrome and color systems.