Visible Light Responsive Dinuclear Zinc Complex Consisting of Proximally Arranged Two d10-Zinc Centers**

Abstract

So far, Zn(II)-based d10 complexes have been known to be colorless unless they are accompanied by chromophoric groups, and therefore both fundamental and advanced photophysical performance of Zn centers of complexes, especially in visible-light regions has been unexplored. Here, we first demonstrate a dinuclear Zn(II) complex that shows visible light absorption using an orbital distributed over closely contacted two Zn centers experimentally determined by X-ray crystallography. A contrastive study demonstrated that intermetallic orbital interaction in dinuclear Zn(II) complex is responsible for capturing visible light to exhibit orangish yellow color, whereas an analogous one without such an interaction is colorless. This work demonstrates that introduction of Zn−Zn interactions to Zn(II) molecules contradicts the common notion that Zn is unresponsive to visible light and expands the photophysical field of zinc chemistry.