Theoretical study of the structure, bonding and electronic spectrum of the tetrameric copper (I) amide complex [CuN(SiMe3)2]4

► DFT calculations reproduce the structure of [CuN(SiMe3)2]4 well. ► TDDFT reproduces absorption spectrum with model complex. ► Excited states show significant Cu-Cu bonding. ► Jahn-Teller effect results in distorted geometry in excited states. ► ΔSCF calculations suggest phosphorescence as mechanism of emission.