Hydrogen bonds and dispersion forces serving as molecular locks for tailored Group 11 bis(amidine) complexes

Abstract

A flexible polydentate bis(amidine) ligand LH2 operates as a molecular lock for various coinage metal fragments and forms the dinuclear complexes [LH2(MCl)2], M = Cu (1), Au (2), the coordination...

Twisted and Disconnected Chains: Flexible Linear Tetracuprous Arrays and a Decanuclear CuI Cluster as Blue- and Green/Yellow-Light Emitters

“…The PBE0 calculations were performed in the gas phase and therefore overestimate the entropy contribution to the free energy for the solid state. Generally, DFT underestimates the stabilization of the larger clusters 3 and II by additional van der Waals interactions which have been found as significant contributions in related binuclear bis­(amidine) coinage complexes . Taking these factors into account, the calculated free energy of aggregation for 3 is within reason for its formation in the crystalline state.…”

“…We became interested in flexible connected bis­(amidines) for linear Cu I complexes because they are extremely versatile ligands, , which have predominantly been employed in Groups 1–4, − 13, and 14 coordination chemistry, together with related catalytic studies. Less, although recently growing interest in late transition metal complexes of bis­(amidines) and bis­(amidinates) is reflected by examples of Groups 8–11 − that have also included multinuclear complex assemblies with more than two metal centers. ,, We chose alkylene-linked bis­(amidinates) not only for designing multinuclear clusters but also for creating defined linear arrangements of Cu I ions that are, due to the flexibility of the linker, substantially bent and therefore adopt structures of helices. The combination of multiple Cu I centers undergoing cuprophilic interactions overcomes their small individual spin–orbit-coupling contributions and can facilitate phosphorescence-based emission of these systems .…”