Theoretical Study On Cadmium (â…¡) And Argentum (â… ) Complexes By Using Atom-Bond Electronegativity Equalization Method

By applying the atom-bond electronegativity equalizationσ-πmodel, i.e. ABEEM-σπmodel, which is based on the density functional theory and electronegativity equalization principle, we performed a large number of quantum chemistry calculations to determine the ABEEM-σπparameters of atoms and bonds in the model with the linear regression and least-square optimization, and a separated program. By employing these parameters, the charge distributions of Cd (Ⅱ) complexes and Ag (Ⅰ) complexes were calculated. The ABEEM-σπcharge distributions is well relevant to those of the quantum chemistry method, and the linear-correlation coefficient are all above 95%.This validates further the rationality and reliability of the ABEEM-σπmodel, and widened the ABEEM-σπmodel's application of transition element in the fifths period.Metallothionein (MT) is a class of proteins that has low molecular weigh, very high cysteine content and can be induced by metal and other complications. The study of metallothionein is gradually recognized because of its unique biological roles at home and abroad in recent years. By applying the new ABEEM-σπparameters of atoms and bonds, we calculated the charge distributions of the active center of ten metallothioneins which is selected from Protein Data Bank (PDB) aboratively. The ABEEM-σπcharge distributions is well relevant to those of the quantum chemistry method, and the linear-correlation coefficient are all above 90%. It is validation that the new ABEEM-σπparameters is applicable to the system of great molecules.By applying the new ABEEM-σπparameters of atoms and bonds, we discussed the activity of the metallothioneins'active center with Fukui Function on the base of the charge distribution, and elicited the conclusion which accord with that of literature. By applying the atom-bond electronegativity equalization-σπmodel, we can calculate the charge distributions of atom and relative area quickly if we know the coordinate of the system. Consequently, we can save a great lot of time when calculating the great metal-biologic molecules.