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Alex Granovsky
gran@classic.chem.msu.su

Did you read the paper below?

http://pubs.acs.org/doi/abs/10.1021/j100342a026

This paper explains some interesting things on this type of analysis.

I only can confirm that this exact printout is by code design.
In my opinion, intrinsic force constants as defined in the paper
above have very little sense, especially for coordinates other
than bond stretches. My guess is thus this is the main reason
why they are not printed.  

Kind regards,
Alex Granovsky




On Wed Sep 26 '12 12:47pm, Vyacheslav wrote
-------------------------------------------
>On Wed Sep 26 '12 1:08am, Alex Granovsky wrote
>----------------------------------------------
>>Hi,

>>how did you specify the z-matrix and a the value of nzvar variable?

>>Regards,
>>Alex Granovsky
>**************************************
>Hi,
>thanks for response.
>The first step is to optimize the structure. Then, in the input I enter the coordinates of the first calculation, internal coordinates in IZMAT and put in NZVAR the number equal to the number of internal coordinates given (for my structures it is always more than 3N-6). Format of coordinates in $Data is irrelevant. One can enter a z-matrix or Cartesian coordinates (COORD=unique), the results are identical. In output file I get a complete set of intrinsic frequencies, while the force constants are for the stretching vibrations only.
>Example of such calculation is attached.
>Best regards,
>                 Vyacheslav

>