Data sets can have any name, but for convenience they should end in ".mop", ".dat", or ".arc" Examples of valid data set names are: H2O.mop, water.mop, water.dat, water.arc, "water dimer.mop". Other names can be used, such as water.mopac, water.archive. If suffixes other than ".mop", ".dat", or ".arc" are used, then the resulting files may have names other than those desired.
This is the recommended sequence for getting MOPAC up and running on a Windows XP platform. It will install the license key and set up the association of MOPAC2007 with the data set in one step.
Make up a data-set with the name of the set being that of the license-key. Thus if the key is "1234567a1234567" then create a file (using e.g. notepad) with the name "1234567a1234567.mop" The file can be empty, it's only the name that is important.
In Windows Explorer, navigate to the file, and right-click on it. Use "Open with" and browse to C:\Program files\mopac. Select MOPAC2009.exe and click on "open". If you want to, put a check in "always use this program to open this kind of file" to associate files ending in ".mop" with MOPAC2009, then click on "ok". MOPAC2009 will start by displaying the End User License Agreement. After reviewing it, if it is acceptable, type " yes" (with the extra space) when prompted. You will probably need to scroll down to see this part.
From then on, whenever you want to run a MOPAC job, either double click on the data set (if you chose to make the association) or right-click and use "Open with" and select MOPAC2007.
In Windows systems, this is referred to as the "command prompt." Although running from the command prompt is straightforward, by preparing a suitable icon the ease of use of the command prompt can be improved. The steps involved in preparing the icon are as follows:
Paste a shortcut to the command prompt on the desktop.
Open the icon by double-clicking.
Right-click on the blue bar at the top and select "properties."
In "Font" chose "Lucida Console", bold, size14.
In "Layout" chose "Screen buffer size" Width: 107; Height: 6000; "Window size"
Width: 107; Height 50; "Window position" -4, -4, uncheck "let system position
window"
In "Colors" chose "Screen background" as white (255,255,255), "Screen text" as
black (0,0,0).
Click on "OK", then chose "Modify shortcut that started this window."
Double click on the icon to get the DOS prompt.
At the dos prompt, C:\>, type the path plus executable name followed by the file to be run. If the path contains spaces, then enclose the path plus executable name in quotation marks, thus:
C:\> "C:\program files\mopac\mopac2007.exe" water
where "water" is the name of the data set, with or without a suffix, to be run. If the location of the MOPAC executable is put in the path, then the command can be shortened to just the executable followed by the data set, e.g.:
C:\> mopac2007 water
If the data set contains spaces, then enclose it in quotation marks, thus:
C:\> mopac2009 "benzoic acid"
For ease of use, put an alias to the location of the MOPAC executable in the startup command sequence (the .bashrc or .cshrc)
Once that is done, the procedure for running a MOPAC job is the same as running from the DOS prompt.
Before the Windows version can be used, make a MOPAC executable icon on the desktop, by copying the executable (use Windows Explorer) and pasting a shortcut on the desktop.
In Windows Explorer, highlight the file(s) to be run. Drag them to the icon for MOPAC, and drop them there. Up to 50 files can be "dragged and dropped" at a time. The jobs will run as if in a batch queue. The progress of each job will be displayed in the MOPAC window. The current job can be paused, by clicking on the "State - pause" option, and resumed by clicking on the "State - resume" option. The "Shut" command (to stop the current calculation by making it appear to run out of time) can be given by clicking on the "Shutdown" key.
To familiarize yourself with the system, the following operations might be useful.
| Benzene | A simple organic compound. |
| Ferrocene | A simple organometallic compound. |
| Polyethylene | A simple polymer |
| Stretching polyethylene | Example of reaction path |
| Diamond | A simple solid |
| Chromium acetate | A complex with a metal-metal bond |
| [Fe(H2O)6]2+ | A low-spin open-shell d5 transition metal complex |
| [Mn(H2O)6]2+ | A high-spin open-shell d5 transition metal complex |
| Fe2(C4Me3)2(CO)3 | A complicated organometallic complex |
| Ni2(Cp)3(CO)2 | Another complicated organometallic complex |
Restarts should be user transparent. If MOPAC does make any restart files, do not change them (it would be hard to do anyhow, as they're in machine code), as they will be used when you run a RESTART job.