The full-featured (no nags, no limits in capabilities) demo version is available for FREE!
STR3DI32 generates the best molecular simulations of single molecules and docked molecular clusters, of any molecular mechanics program currently available. If you want to do serious, sophisticated molecular modeling, like working with biomolecular clusters, including chelated metal atoms, and the many other things that the student versions of software packages cannot do, then you will want to use STR3DI32.
If you want to do modern molecular modeling, in which molecular structural features are generated in direct response to the structural and stereo-electronic features of the molecule being simulated, and NOT by inflexible templates, then consider using STR3DI32.
Try using one of the other molecular modelers to search a large complex protein structure for important features like non-delocalized amide linkages! Only STR3DI32 can do that successfully.
The advanced structure analytical algorithms of STR3DI32 have been exhaustingly tested, and shown to be vastly superior to others, in detecting subtle stereo-electronic effects embedded in diffraction generated coordinate data, like delocalization, aromaticity and anomeric effects. No other molecular mechanics based program can help you to understand the interplay of structure and reactivity because they do NOT perform their calculations with explicit inclusion of lone pair interactions. For example, the ONLY molecular mechanics program that can predict the relative nucleophilicities of the hydroxyl groups in a polyol is STR3DI32.
Did you know that the vast majority of quantum mechanical theoretical studies start with molecular models generated by molecular mechanics? And that even when a low-end MM program is used to make the initial model, the QM manipulations hardly ever result in any change in the structure? Did you know that it is almost impossible to generate a realistic molecular model, ab initio, using any QM method? And, when you do your simulation, did you use the right basis-set, the best set of approximations, to get the best model?
And, while we are here, remember that........
Windows 7 users should remember that STR3DI32 is a 32 bit program. Tell us about any compatibility issues that you might encounter.
We have run STR3DI32 under Windows 7, with full functionality, after adjusting the UAC (User Account Control) feature to "never notify". This allows STR3DI32 to write freely to the HDD (as it needs to). A less desirable way is to right click the program and use the “run as administrator” option. However, there will still be interruptions by the O/S, and you will find that there are many programs you are going to have to run this way.
The Windows 7 UAC (User Account Control) feature is, in fact, badly flawed. We have Windows 7 on a single user computer and the Owner/Administrators have full control over drive C:. We copied a small text file to drive C:\ (the root dir.) and tried to make one small change in it. With UAC on, and at the intermediate setting, we were unable to save the modified file, no matter what we did. With UAC off, we were able to use the computer normally. The Windows 7 UAC (User Account Control) feature is badly constructed and needs to be fixed.
Another way to handle this read/write permission problem in Windows 7 is to take full control of the drive that you, or your application, wish to write data to.
Most emulators that run Windows in Apple Macs will run STR3DI32 almost as fast as it runs in a PC with Windows.
We strongly recommend that Windows XP users use Internet Explorer 7, instead of IE8. Users of the Windows 7 O/S are forced to use IE8. Hopefully, Microsoft will attend to it IE8's problems very soon, proactively, instead of playing “catch up” with FireFox.
In the interim, for Windows 7 and IE8, we have found that turning off “Smart Screen Filter” (found at Tools – Internet Options – Advanced – Security) dramatically speeds up IE8's opening of URLs, both on you HDD and abroad. Can you just imagine 300,000,000 computers asking the Microsoft website, all at the same time, if a site is OK to browse? Chaos and slow responses must be the result.
We have added a short tutorial on drawing molecules using STR3DI32 at the STR3DI32 FAQ site. Take the time to find out more about STR3DI32 and remember to visit the STR3DI32 FAQ for hints, user/program tips and additional help.