Theoretical study of ht-[(ph)Pt(μ-PN)(μ-NP)PtMe2](CF3CO2) structure as a heavy dimer complex and comparison of results with experimental X-ray data

DFT calculations performed using Amsterdam Density Functional (ADF 2009.01b) program to estimate best geometry of an unsymmetrical cationic organo-diplatinum complex containing two bridging 2-diphenylphosphinopyridine,(PN), ligands and a platinum-platinum donor–acceptor bond, ht-[(ph)Pt(μ-PN)(μ-NP)PtMe2](CF3CO2), as a moderately heavy dimer complex of platinum(II). The obtained geometry is in excellent agreement with the crystallographic data. Energy is in all cases about 12–15 kcal mol−1. For the LDA (XC potential in SCF) the DZ and TZ2P basis sets have been used. Furthermore, for the GGA(BLYP), GGA(BP) and GGA(PW91) method, the DZ basis set have been just used, due to the cost of calculations. The result showed that surprisingly the simple LDA(TZP) method has the minimum of energy, comparing the others. All the attempts for optimizing the mentioned dimer using B3LYP and OLYP methods failed