The influences of skeleton metal atoms on electronic structures and physical - Chemistry properties of Keggin anions

The electronic structures of Keggin anions (PM12 O-40) (n -) ( M = Mo, W, V ), (PMo9 W-3 O-40)(3 -) (PMo9 V-3 O-40)(6 -) have been calculated by the Di screte Variational Method coupled with the first principal Density Function al Theory (DFT - DVM). The influences of skeleton metal atoms on the charge distribution, bonding effects, stability, redox properties are discussed. The results show that skeleton metal atoms have influence on the charge dis tribution and bonding effects. The relative sequence of stability is: (PW12 O40)(3 -) > (PMo12O40)(3 -) > (PV12O40)(15 -). We developed the two - facto rs method for determining the escape ability of lattice oxygen atoms and th e LUMO electronegativity. The relative sequence of redox properties has the n been shown to be: (PV12O40)(15 -) > (PMo12O40)(3 -) > (PW12O40)(3 -). The replacement effects of Mo with W and V are discussed. The stability of Keg gin units is strengthened, but the redox ability is weakened when the Mo at oms are replaced by W. Tne stability is weakened and redox property is stre ngthened when the Mo atoms are replaced by V.