Factors influencing the 17O quadrupole coupling constant in bridging oxygen environments

Abstract

Ab initio calculations were performed on the series of clusters [(OH) 3MOM(OH) 3] −2 where M=B, Al, and Ga, (OH) 3MOM(OH) 3 where M=C, Si, and Ge, (OH) 2OMOMO(OH) 2 where M=P and As, and (OH)O 2MOMO 2(OH) where M=S and Se. These clusters were constructed to model the effect of changing the coordinating cation and coordinating cation–oxygen distances on the bridging oxygen 17O quadrupole coupling constant. For all clusters studied, we observed a general trend that the magnitude of C q increases linearly with increasing cation–oxygen bond distance and cation group number, suggesting that group number and cation-bridging oxygen distance can serve as a better predictor of the bridging oxygen quadrupole coupling constant than electronegativity differences.