A study on the electronic and charge transfer properties in tin phthalocyanine (SnPc) derivatives by density functional theory

The carrier transport properties of tin phthalocyanine (SnPc) derivatives have been investigated at DFT/B3LYP/(6-31G*, LANL2DZ) level. Contributions from the Boron and Nitrogen atoms are found to be predominant in the HOMOs. Moreover, the systems SnPcBN3, SnPcBN4 and SnPcBN5 have lower LUMO energy in comparison to SnPc. Introduction of BH (at position 1, 2 and 3) and NH (at position 4) onto the SnPc molecule induces the increase in both the vertical ionization potential (IPv) and vertical electronic affinity (EAv) for SnPcBN3, SnPcBN4, SnPcBN5 versus SnPc. These results indicate the increased injection barrier for hole and decreased injection barrier for electron transfer. On the other hand, both IPv and EAv for SnPcBN1, SnPcBN2 are decreased to SnPc revealing the decreased and increased injection barrier for hole and electron transport, respectively. It has been predicted that SnPcBN3, SnPcBN4, SnPcBN5 would be better electron transfer materials while SnPcBN1, SnPcBN2 behave as better hole transporter.