The Computer Program for Chemical Thermodynamics and Energy Release Evaluation
 
Frequently Asked Questions
 
How does one directly enter more than one molecule on the Descriptor Grid Screen?
  It is possible to enter a number of different molecules on the Descriptor Grid screen by choosing Benson groups or other molecular descriptors. Care should be taken however to enter each molecule in its own column. Do not enter more than one molecule in any one column. Data entry is demonstrated in the Demo section of the web site and is also further explained in the CHETAH user manual.
 
What is the correct way to enter a balanced reaction?
 

Do not use the count entry on the descriptor grid to balance your equation. The count entry only serves as a counter to the number of groups and not molecules. Use this screen to describe each reactant and product compound or element on the molecular descriptor grid screen. Once this is done, choose the reaction thermochemistry icon. This results in a screen where the user identifies each chemical as a reactant or product. The user also enters the molar stoichiometric coefficients for the reaction. The program will generate an error message if the reaction is not balanced. This process is also demonstrated in the demo section of the web site and is further explained in the users manual.

 
The program seems to stall once I enter a group and its count. I have trouble entering the next group in the descriptor grid. Why does this happen?
 

Do not use the count entry on the descriptor grid to balance your equation. The count entry only serves as a counter to the number of groups and not molecules. Use this screen to describe each reactant and product compound or element on the molecular descriptor grid screen. Once this is done, choose the reaction thermochemistry icon. This results in a screen where the user identifies each chemical as a reactant or product. The user also enters the molar stoichiometric coefficients for the reaction. The program will generate an error message if the reaction is not balanced. This process is also demonstrated in the demo section of the web site and is further explained in the users manual.

 
The program seems to stall once I enter a group and its count. I have trouble entering the next group in the descriptor grid. Why does this happen?
 

This is caused by the position of the cursor. If you modify the entry in the count column, you should make sure that you move the cursor back to the group column, if you wish to enter additional groups. Keeping the cursor in the count column disables the entry of additional groups.

 
Occasional Installation Problems
 

The following are known problems that have shown up on some computer systems for CHETAH Version 9.0.

I am running the Vista operating system. When I install the program and try to run it, I get an error message related to vsprint.ocs and the program does not run. What do I do?

After your installation is otherwise finished, please take the additional steps outlined in the Vista Compatibility Guide.

 
The following are known problems that have shown up on some computer systems for CHETAH Version 8.0 and earlier.
 

1. I get the following error when I try to run SmilesInput: "Put err.dat and other.dat and .txt files in \chetah\ dependency directory". What do I do?

  Method 1:Method 1: Download the zip file from below and unzip it to the CHETAH 8 folder and overwrite all files when prompted.
Smiles.zip Download Updated Smiles Input (updated : 05/31/05, Zip File Instructions)
 
 

Method 2: Create a .dac file by entering a molecule into the Molecular grid and click on File then Save as. Give a file name and save it. Next click on File then Open and browse to the file just saved and open it. Now try Smiles Input.

 

2. Component 'mscomct2.ocx' or one of its dependencies not correctly registered: a file is missing or invalid. What do I do?

 

Step 1: Download mscomct2.ocx and place it under the /Program Files/Chetah 8/ folder

mscomct2.ocx Download Missing File (updated : 05/31/05)
 
 

Step 2: Click on the "Start" button and then click on Run. Type the following command to register the file:

regsvr32 "C:\Program Files\CHETAH 8\mscomct2.ocx"
 
3. ”VSPRINT.OCX” is missing. What do I do?
Some users might need to download the following system file to the Windows/System folder on their computer. VSPRINT.ocx . Users should check with the system administrator for system privileges if the file fails to download successfully.
 
 
 
Opening a Zip File: If your operating system does not recognize the downloaded zip file then you might need to install WinZip® (or similar software) from http://www.winzip.com in order to run the service pack on your computer. A trial version of the software can be downloaded from http://www.winzip.com/downwz.htm.
 
 

 

 
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Date last changed: October 28, 2009 9:05 AM
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