Structural and Energetic Study of Cisplatin and Derivatives: Comparison of the Performance of Density Funtional Theory Implementations

P.D. DANS; A. CRESPO; E.L. COITIÑO; D.A. ESTRIN

journal of chemical theory and computation

American Chemical Society

Lugar: Columbus, OH; Año: 2008

1549-9618

            In this work, we compare the performance of different DFT implementations, usinganalytical and numerical basis sets for the expansion of the atomic wave function, in determiningstructural and energetic parameters of Cisplatin and some biorelevant derivatives. Characteriza-tion of the platinum-containing species was achieved at the HF, MP2, and DFT (PBE1PBE,mPW1PW91, B3LYP, B3PW91, and B3P86) levels of theory, using two relativistic effectivecore potentials to treat the Pt atom (LanL2DZ and SBK), together with analytical Gaussian-typebasis sets as implemented in Gaussian03. These results were compared with those obtainedwith the SIESTA code that employs a pseudopotential derived from the Troullier-Martinsprocedure for the Pt atom and numerical pseudoatomic orbitals as basis set. All modeledproperties were also compared with the experimental values when available or to the besttheoretical calculations known to date. On the basis of the results, SIESTA is an excellentalternative to determine structure and energetics of platinum complexes derived from Cisplatin,with less computational efforts. This validates the use of the SIESTA code for this type of chemicalsystems and thus provides a computationally efficient quantum method (capable to linear scalingat large sizes and available in QM/MM implementations) for exploring larger and more complexchemical models which shall reproduce more faithfully the real chemistry of Cisplatin inphysiological conditions.