From chemistry-request@ccl.net Wed Nov 6 08:11:12 1991 Date: Wed, 6 Nov 1991 07:47 EST From: "DONALD B. BOYD" Subject: coordinates from z-matrices To: chemistry@ccl.net Status: R Regarding the question from Katrina Werpetinski , >Does anyone have a (preferrably fortran) algorithm for >converting a Z-matrix (ie bond length, angle, and >dihedral angle of a set of four atoms) into cartesian >coordinates? The QCPE at Indiana University, Bloomington, IN 47405, has many versatile FORTRAN programs for doing this operation. Contact Mr. Richard Counts, Director, QCPE, countsr@iubacs.bitnet. From: BOYD DONALD B (MCVAX0::QSAR) To: VMS MAIL ADDRESSEE (INT::"chemistry@ccl.net") cc: BOYD DONALD B (MCVAX0::QSAR) From chemistry-request@ccl.net Wed Nov 6 08:39:20 1991 Date: Wed, 6 Nov 1991 07:20 CDT From: Andy Holder Subject: Internal to cartesians. To: CHEMISTRY@ccl.net Status: R A FORTRAN subroutine to perform this task is found in AMPAC. It is called INTCAR and is a subroutine in the module GMETRY. The code is derived from some ancient stuff written by Michael Dewar. Andy Holder =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= DR. ANDREW HOLDER Department of Chemistry || BITNET Addr: AHOLDER@UMKCVAX1 University of Missouri - Kansas City || Internet Addr: aholder@vax1.umkc.edu Spencer Chemistry, Room 502 || Phone Number: (816) 235-2293 Kansas City, Missouri 64110 || FAX Number: (816) 235-1717 =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= From chemistry-request@ccl.net Wed Nov 6 16:52:08 1991 Date: Wed, 6 Nov 91 16:23 EST From: "Scott Le Grand" Subject: Superimposition Algorithm questions To: chemistry@ccl.net Status: R In the Journal of Computational Chemistry, Vol 9, No 6, 596-599 (1988), Liu and Van Rapensbusch present a rapid algorithm to superimpose two sets of atomic coordinates. I am trying to implement this algorithm in one of my programs, but I am finding their description a little too sketchy to be useful. Specifically, they use three terms F , F theta phi and F which are vital for finding a rotation matrix which will superimpose psi the two sets of coordinates in question, but are not actually defined anywhere in the paper. Secondly, they claim that they can set the results of equation 7 by a simple position adjustment which they do not describe. Has anyone out there tried to implement this algorithm and figured out what the three F terms are and what the adjustment is? If you haven't read the paper, please disregard. It's probably not worth your time to puzzle it out... Scott Le Grand