TURBOMOLE Users Forum
TURBOMOLE Modules => Statpt => Topic started by: chburger on July 08, 2007, 08:48:23 PM
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I inquired a problem with statpt:
While aoforce clearly evidenced only one imaginary frequency, statpt (V5-9-1 18 Apr 2007) believes that there
are two: Do I miss something here?
Regards
Peter
relevant part of the control file:
$nvibro 93
$vibrational spectrum
# mode symmetry wave number IR intensity selection rules
# cm**(-1) km/mol IR RAMAN
1 a -1078.97 0.00000 YES YES
2 0.00 0.00000 - -
3 0.00 0.00000 - -
4 0.00 0.00000 - -
5 0.00 0.00000 - -
6 0.00 0.00000 - -
7 0.00 0.40029 - -
8 a 56.97 1.10216 YES YES
9 a 80.77 11.72408 YES YES
10 a 84.74 3.16747 YES YES
statpt output:
Found initial Hessian matrix in $hessian section
Number of zero Hessian eigenvalues: 0
5 first eigenvalues:
-0.06471367 -0.05304723 0.00080796 0.00150790 0.00939792
Eigenvalue of transition vector: -0.06471367
#######################################
WARNING: HESSIAN HAS WRONG INERTIA!!!
NUMBER OF NEGATIVE EIGENVALUES
2
#######################################
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What you see in the output of aoforce are vibrational frequencies, i.e. square roots of eigenvalues of the mass weighted Cartesian Hessian. In the statpt output you see the eigenvalues of the Hessian matrix in internal coordinates. Although usually there is a close correspondence between vibrational frequencies and normal modes of internal Hessian this need not to be always the case.