Summary: Relativistic Effect

 Hi,
 I would like to thank everyone who replied to my question. The following is a
 summary of the responses. I hope this summery can also help others.
 This is my original question:
 I want to study geometries of some molecules with Pb and Sn. I know that for
 heavy atoms I need to include the relativistic effect in my calulation but I do
 not know what method and basis set is the best for these heavy atoms. I have
 several articles discussing relativistic effect but would like suggestions of
 articles and books also.
  Best regards,
  Pornpun Rattananakin
 --
 Sorry for the self-promotion, but I might suggest the new cc-pVnZ-PP
 (n=D-5) basis sets for these
 elements that use very accurate relativistic effective core potentials.
   These sets are
 described in  JCP 119, 11099 (2003) and JCP 119, 11113 (2003) and are
 available
 for download on the EMSL basis set website
 (http://www.emsl.pnl.gov/forms/basisform.html)
 regards,
 Kirk Peterson
 --
 Hi,
 If you wanted to cut down on calculation time, I can tell you that the
 Stuttgart pseudopotentials have included spin-orbit coupling effects in
 the parameterization.  They work reasonably well.  Look for papers by
 Dolg, Stoll and Preuss.
 Hope that helps,
 Sean Hughes
 Centre for Research in Molecular Modeling (CERMM)
 Dept. Chemistry and Biochemistry
 Concordia University
 7141 Sherbrooke St. West
 Montreal, Quebec
 Canada
 H4B 1R6
 Tel: (514)-848-2424 ext.4260
 Fax: (514)-848-2868
 --
 Dear Pornpun Rattananakin,
 Perhaps Erik van Lenthe's Ph.D. thesis on the relativistic ZORA method,
 as implemented in ADF, could be of interest to you:
 http://www.scm.com/Doc/vlenthe.pdf
 I hope this is relevant for you. If you want more info on this, let me
 know.
 Best regards,
 Stan van Gisbergen
 --
 I study Ruthenium complexes using B3LYP/LanL2DZ. The LanL2DZ basis set includes
 a pseudopotential for the inner electrons of the Ru - this takes care of
 the relativistic effect as well as speeds up the calculation.
 I find the books by C. Cramer and F. Jensen very useful: "Introduction to
 Computational Chemistry" and "Essentials of Computational
 Chemistry" (both
 > from Wiley).
 Noel
 --
 "So the LanL2DZ basis set is the best one for B3LYP method, isn't it?"
 Well, I don't know if that's true. I think you need a basis set with an
 effective core potential (ECP).
 If you look at http://www.gaussian.com/g_ur/m_basis_sets.htm and search
 the page for the word ECP you find the following basis sets:
 SHC, CEP-4G, CEP-31G, CEP-121G, LanL2MB, LanL2DZ, SDD.
 Which is best?? Well, LanL2DZ is better than LanL2MB. And all of the CEPs
 are the same after the second row (so they are probably not good for you).
 Some people using the SDD ones. I recommend testing LanL2DZ and SDD versus
 a crystal structure, or finding some reference where results from different
 ECPs are compared.
 Noel
 --
 Dear Pornpun
 I good idea is to use ECP potentials for your studies. Their computational cost
 is reasonable and offer good results.
 A very good book on relativistic effects is the one of Krishnan
 Balasubramanian, Relativistic effects in Chemistry.Also the Review article of P.
 Pyyko, Chem. Rev 88, 563 1988, describes in brief topics
 concerning the effect of Relativity on Molecular Gem. and other Properties. Also
 you will find a reach source of articles based on
 relativity.
 The best
 Aggelos Avramopoulos PHD
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