Subject: Q:warning in G03 frequency output

From: Georgina Aitken <g.d.c.aitken)at(sussex.ac.uk>
Date: Mon, 29 Nov 2004 16:06:01 +0000

Dear CCLers,

I am a PhD student and have been getting the following warning messages in
the thermochemistry section of my Gaussian frequency outputs for various 
divalent Pb-ligand complexes:

"Principal axes and moments of inertia in atomic units:
                           1         2         3
     EIGENVALUES --  4494.802316560.791727501.25369
           X            0.99998   0.00350   0.00560
           Y           -0.00289   0.99445  -0.10519
           Z           -0.00593   0.10517   0.99444
 This molecule is an asymmetric top.
 Rotational symmetry number  1.
 Warning -- assumption of classical behavior for rotation
           may cause significant error
 Rotational temperatures (Kelvin)      0.01927     0.01320     0.01155
 Rotational constants (GHZ):           0.40152     0.27508     0.24059
 Zero-point vibrational energy     647177.6 (Joules/Mol)
                                  154.67917 (Kcal/Mol)
 Warning -- explicit consideration of  23 degrees of freedom as
           vibrations may cause significant error "

Does this mean that the zero point energy correction is not reliable? What
can I do about it?

Thanks in advance,

Georgina Aitken