Uv absorption inmetal decorated boron nitride flakes: A theoretical analysis of excited states

© Informa UK Limited, trading as Taylor & Francis Group. The excited states of singlemetal atom(X=Co, Al and Cu) doped boron nitride flake (MBNF) B 15 N 14 H 14 -X and pristine boron nitride (B 15 N 15 H 14 ) are studied by time-dependent density functional theory. The immediate effect of metal doping is a red shift of the onset of absorption from about 220 nmfor pristine BNF to above 300 nm for all metal-doped variants with the biggest effect for MBNF-Co, which shows appreciable intensity even above 400 nm. These energy shifts are analysed by detailed wavefunction analysis protocols using visualisationmethods, such as the natural transition orbital analysis and electron-hole correlation plots, as well as quantitative analysis of the exciton size and electronhole populations. The analysis shows that the Co and Cu atoms provide strong contributions to the relevant states whereas the aluminium atom is only involved to a lesser extent