From wolpert: at :neon.chem.utk.edu Mon Jan 24 12:52:47 1994 Received: from neon.chem.utk.edu for wolpert %-% at %-% neon.chem.utk.edu by www.ccl.net (8.6.4/930601.1506) id MAA25882; Mon, 24 Jan 1994 12:47:12 -0500 Received: by neon.chem.utk.edu (4.0/1.34) id AA14552; Mon, 24 Jan 94 12:52:05 EST Date: Mon, 24 Jan 94 12:52:05 EST From: wolpert(+ at +)neon.chem.utk.edu (Edward Wolpert) Message-Id: <9401241752.AA14552 "-at-" neon.chem.utk.edu> To: CHEMISTRY;at;ccl.net Subject: Request: Prog or code to convert xyz f. const to int. Netters- I'm trying to write a little program to convert force constants from xyz co-ordinates to internal co-ordinates without having to worry about redundencies. This code would assume the force constants in xyz and b-matrix already exist. (They come from hondo 8.2) I'm also interested in programs that are freely available that do this already. Due to my limited funding, I'm not currently able to get the proper programs from QCPE that do this. I do not need to generate the vibrational frequencies, just convert force constants from one format to another. I know that the following should work: F(int) = B x F(xyz) x B-1 where B is the b-matrix, and B-1 is the transposed b-matrix. However, I noticed that in hondo, they seem to use the inverse B matrix instead. I would like to use the 'normal' b-matrix for such work. Also, to be able to convert the units within the program. If such a program exists in the public domain, please send me information on it. If not, I would like suggestions on how I can write such a program. Once written, I will be more than happy to put the source code in the public domain, giving credit to those who help. My current work is in C, but current fortran code is also useful. Virtually, Edward Wolpert -------------------------------- wolpert-!at!-neon.chem.utk.edu | Graduate Chemistry Student wolpert-: at :-lead.chem.utk.edu | wolpert#* at *#osti.slip.utk.edu | System Administrator wolpert "-at-" utkux.utk.edu | wolpert: at :novel.chem.utk.edu | Systems Programmer wolpert -A_T- utkvx.utk.edu | pa153568 \\at// utkvm1.utk.edu | Still waiting for Godot... --------------------------------