Effect of micelles on speciation of ternary complexes of nickel(II) with L-arginine and L-histidine

Abstract A computer assisted investigation has been made pH-metrically on the speciation of mixed ligand complexes in ternary systems consisting of nickel(II), L-arginine and L-histidine in micellar media. The existence of different ternary species is established from modelling studies using the computer program MINIQUAD75. The relative concentrations and stabilities of the ternary species are compared with those of binary species. The extra stability associated with the ternary complexes is attributed to factors such as charge neutralization, chelate effect, stacking interactions and hydrogen bonding.