Subject: HYPERCHEM, CACHE, GAUSSIAN< ROCKET-SCIENCE

From: <[email-masked]>
Date: Fri, 3 Jun 94 12:47:45 -0400

Netters:  Re:HYPERCHEM

It's a great package in my opinion.  It's not perfect in my view, but for the	
PC enviroment it does more than most others I am familiar with.  I would 
compare it against George Purvis' Mac CACHE package at Tektronix. Two very good 
packages!  I would like to see a bit more flexibility in some of HYPERCHEM's 
approach to some of its features.  I share the concern related to conjugate
gradient optimisation for semi-empirical, and in cartesian coordinates.  When
such an approach is taken for floppy molecules such as dyes, a lot of cpu time
gets used!  Internal coordinates using a Newton-Raphson approach  is more 
powerful than anything we have used for the past 10 years. Baker's EF routine,
particularly in MOPAC-93, is hard to beat in our experience on PC's and work
stations.

Now in good fun, I have to take a friendly poke about the recent comment about
what IOP(4/20=7) means in Gaussian: 1) Most places have source. 2) All places
SHOULD have documentation.  I realise things are getting to "If I have to read
the documentation, the program's not well written,"  but you gotta do it!
IOP(4/20=N) is described therein, though not explicitly for N=6,7,8. The 
documenation is a bit behind, as it usually reflects the text at the beginning
of each block of Links for the source....so Rocket-Science is not required, just
a little logic.

John McKelvey
Eastman Kodak