ALL-ELECTRON AB-INITIO CALCULATIONS ON TETRAMETHYLTIN

All-electron ah initio (nonrelativistic) calculations on tetramethylti n, Sn(CH3)(4), have been carried out at the SCF, MP2, and MP4 levels o f theory. At the MP4 correlation level the Sn-C bond distance is predi cted to be 2.144 Angstrom, in excellent agreement with experiment. Our calculations indicate that useful results can be obtained even at the SCF level, due to a possible cancellation of relativistic and correla tion effects, provided that a good quality basis set for the metal is employed.