Thanks to Dora Schnur from Monsanto we have a very useful addition to our software archives. The program was written for UNIX System V for Silicon Graphics, so other C's may require some small modifications. Also, you are required by the Copyright of the program to notify dmschn@bb1t.monsanto.com (Dora Schnur) that you have a copy of the program. Just send a short note with your name and address to dmschn@bb1t.monsanto.com that you retrieved the program. It does not bind you to anything, but is a condition for releasing the program to the general public. From readme file: "mm2_params" is a C language program which attempts to remedy missing parameter messages from either MM2(87) or MM3. Often, MM2/MM3 will be unable to process a structure because required parameters are missing. One method of supplying crude parameters is for the researcher to manually select them from known parameters based on their knowledge of the similarity of atom types, using atom number, hybridization, electronegativity, etc. "mm2_params" attempts to replicate this similarity matching in an automated, consistent fashion. "mm2_params" does NOT produce optimized parameters - it produces a first guess based solely on similarities, which is intended to be used as an adequate starting point for optimization by the researcher. For method details, see The Journal of Computational Chemistry (1991) 12(7), 844, "Development of an Internal Searching Algorithm for Parameterization of the MM2/MM3 Force Fields". You can download the program by using ftp in the following way: %ftp www.ccl.net (or ftp 128.146.36.48) Name: anonymous Password: Your_e-mail_address ftp> ascii ftp> cd pub/chemistry/mm2_params ftp> mget * ftp> quit If you do not have ftp, you may still obtain the program by using our e-mail interface. Send the following message: send ./mm2_params/mm2.site_parameters from chemistry send ./mm2_params/posting from chemistry send ./mm2_params/mm2_params.c from chemistry send ./mm2_params/mm2_params.make from chemistry send ./mm2_params/readme.mm2_params from chemistry send ./mm2_params/thiophene.mm2 from chemistry send ./mm2_params/thiophene.para from chemistry send ./mm2_params/thiophene_mm2.out from chemistry send ./mm2_params/utility.c from chemistry send ./mm2_params/utility.h from chemistry to OSCPOST@ccl.net or OSCPOST@OHSTPY.BITNET and the files will be automatically forwarded to you by e-mail. Thanks again to Dora Schnur for this needed contribution. Jan Labanowski Ohio Supercomputer Center jkl@ccl.net