Ab initio and density functional theory studies on vibrational spectra of palladium (II) and platinum (II) complexes of methionine and histidine: effect of theoretical methods and basis sets.
The vibrational spectra of methionine and histidine-containing palladium (II) and platinum (II) complexes, cis-M(Met)X2 and cis-M(His)X2 (M = Pd and Pt; X = F, Cl, Br and I; Met = methionine, His = histidine), have been systematically investigated by ab initio Restricted Hartree-Fock (RHF) and density functional B3LYP methods with LanL2DZ and SDD basis sets. The geometries of cis-Pd(Met)Cl2, cis-Pt(Met)Cl2, cis-Pd(His)Cl2 and cis-Pt(His)I2 optimized and vibrational frequencies and IR intensities of cis-M(Met)Cl2 and cis-M(His)Cl2 (M = Pd and Pt) calculated are evaluated via comparison with the experimental values. The vibrational frequencies calculated show that the methods, rather than basis sets, affect the accuracy of the calculation. The best results that can reproduce the experimental ones are obtained at B3LYP level without any scale factor used. The vibrational frequencies of cis-M(Met)X2 and cis-M(His)X2 (M = Pd and Pt; X = F, Br and I) that have not yet been experimentally reported are predicted.
State Key Laboratory of Coordination Chemistry, Coordination Chemistry Institute, Nanjing University, 210093, PR China.
Gaosheng
G
Yang
Chen
C
Jin
Jing
J
Hong
Zijian
Z
Guo
Longgen
L
Zhu
D006639:Histidine / Q000737:chemistry*; D008715:Methionine / Q000737:chemistry*; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D010165:Palladium / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D014732:Vibration
D010984:Platinum; D006639:Histidine; D010165:Palladium; D008715:Methionine