Re: CCL:scaling MP2 freq.



 The original poster asked about scaling factors to be applied to mp2/6-31g**
 calculated frequencies. He asked if our mp2/6-31g* scaling factor is
 applicable and if the scalinf factor varies with basis set.
 Our worl in this area, which is nearing completion, indicates that the mp2
 level of theory is not particularly sensitive to basis set in predicting
 frequencies. While the 6-31g** basis set was not studied, we have data for the
 6-311g** basis set. The appropriate scaling factor for the mp2 level of theory
 with this basis set is 0.9496 (with about the same overall RMS error as wefound
 for the mp2/6-31g* level of theory).
 We have actually studied a very extensive range of methods (including DFT) with
 various basis sets. If readers would like further information then please
 contact me.
 Hope this is of some assistance,
 Kind Regards,
 Anthony P. Scott
 Research Officer
 Computational Chemistry Group
 Research School of Chemistry
 Australian National University
 Canberra, ACT, Australia