Subject: Problems with point group recognition in MOPAC 7.0

From: [email-masked] (Joachim Schulte)
Date: Tue, 8 Aug 1995 14:11:33 +0200 (CST)

Dear Ladies and Gentlemen, 

With Mopac 7.0 I have some problems
concerning the recognition of some point groups. Provided with an 
icosahedral C60 geometry MOPAC does not recognize any point group, 
not even a subgroup of Ih. The output simply is '????'. The degeneracy
scheme of the molecular orbital energies is looking correct (3-, 4- and 
fivefold degeneracies). This happens both for cartesian coordinates 
and Z-matrix coordinates (Mopac and Gaussian style). 
But also with simpler molecules there seem to be problems, e.g. 
cyclopentadienyl-anion. 
Mopac returns C5H in that case.  Other molecules, as benzene or 
methane are correctly(D6H and TD). 
These problems seem to be hardware-independent (Tried on a Pentium
running Linux and a DECstation running Ultrix).   

I want to do some calculations on fullerenes and I am therefore 
very interested in getting Mopac to recognize molecular symmetry 
correctly. 
Are problems like the ones mentioned above already known? 

Sincerely Yours

Joachim Schulte ([email-masked])