Exponential decay of a charge transfer induced by coordination in organometallic complexes

Abstract

In the series of organometallic complexes N3P2(X)5P-SPACER-MLn X= CI and OR, MLn= organometallic fragment, the A31 P-NMR coordination chemical shift parameter correlates with the length of the spacer, decaying exponentially with the length of it. The bridging spacers behave like a molecular wire showing dependence of the charge transfer with the distance, similar to electron transfer in donor-acceptor systems. Extended Hückel molecular orbital calculations on the model series N3P2(X)2 P-SPACER-MLn X=CI~ and OH molecules shows that the changes of the Mulliken charges on the phosphorus and metal atoms upon coordination exhibits also an exponential dependence with the length of the spacer.