CCL:G: Difference between Gaussian 09's SVP,TZVP and def2-svp, and def2-tzvp?

 Sent to CCL by: Mikael Johansson [mikael.johansson/a\iki.fi]
 Hello Bradley and All,
The older Karlsruhe/Ahlrichs basis sets (def-XXX) shouldn't be used for new work. The def2 bases are more systematic and well behaved. That said, they are in general larger as well. In your specific case, the main difference between def-TZVP and def2-TZVP is that the def2 are polarised by one additional angular momentum compared to the def bases for most elements. 
 For explicit differences, utilise for example:
   http://www.cosmologic.de/basis-sets/basissets.php
For a thorough discussion, see the original paper on the def2 basis sets, Weigend & Ahlrichs, PCCP 7 (2005) 3297, http://dx.doi.org/10.1039/B508541A
The paper should convince you to use the def2 basis sets. The errors of the double-zeta def2-SVP are usually smaller than for the older triple-zeta def-TZVP, for example. 
 Cheers,
     Mikael J.
     http://www.iki.fi/~mpjohans/
 On Wed, 13 Nov 2013, Bradley Welch bwelch5[-]slu.edu wrote:
 
 Dear all,
 I have some organometallic complexes I'd like to do an optimization on before
 I do some additional calculations (mainly energetics). From what I understand
 the SVP and TZVP basis sets in Gaussian 09 are older iterations of the
 aldrich basis sets. Barring age (and different exponents), are there any
 other differences in terms of extra functions on the newer ones? Before doing
 the optimization, I wanted to get an idea of time by doing a single point on
 the system with both sets of basis sets. I ran one with TZVP (the built in
 one in gaussian) on C,H,N,O and Br and used the def2-tzvp&pseudo potential
 on
 platinum. I reran the same molecule but with the updated basis sets on
 C,N,H,O,Br and def2-tzvp&pseudopotential on Pt. For the built in one I got a
 total of 2224 basis functions. With the def2 ones from the EMSL I got 3208
 basis functions. The calculation using the def2 ones also took significantly
 longer.
 I'm including in this email dropbox links to my input files. Maybe my issue
 is I forgot a blank space or something like that.
 (using def2 basis sets from EMSL)
 https://www.dropbox.com/s/0x0wfs1ju8vxitw/dimerdef2pseudo.inp
 (using built in TZVP on C,H,N,O,Br, def2&pseudopotential on Pt)
 https://www.dropbox.com/s/5rs6nnbpnkg7in4/dimercomp3pipi.inp>;