Preface to AMPAC 8 Manual

Dear Colleagues,

We are very pleased to release AMPAC™8 to our user community! It is the result of many months of development and testing and is (not unexpectedly!) the best version we have ever released.

One of the most important additions to AMPAC is the online manual that you are now reading. This manual has been converted to this electronically readable format as well as having been extensively revised and updated. The manual is accessible from our graphical user interface, making it even more convenient to use and consult. This conversion and updating has taken some time and a good bit of effort, but we think the resulting enhanced usability will help you apply AMPAC in your research endeavors more productively. Avoiding a printed version of the manual will also allow us to reduce costs and keep it more or less instantly up to date and available on our website for quick download.

Our graphical user interface (AGUI) has improved substantially as well. Our new dialog for managing CI options and viewing results will make this newly expanded method (previously the province of specialists only) understandable and informative. A significant number of new display options have also been added including displays of 2D reaction grids and IRC/annealing/reaction coordinates, and the program is completely compatible with Gaussian03®. You can also now see multiple cubes and surfaces on the screen at the same time. AGUI is still intuitive and easy to use, but more powerful than ever.

AMPAC itself has come a long way. It has been re-coded for larger systems and all calculations will much more efficiently use memory. AMPAC also has some new tools for reaction studies (CHN, LFORCE, grid) that will speed up location of transition states. The new AMPAC 8 is once again faster than the competition, more capable than any competitor and simply the best semiempirical solution available.

Many thanks,

Andrew J. Holder

President

May 13, 2004