Electronic Structure and Optical Response of Zn‐Based Metal–Organic Frameworks

Abstract

AbstractThe results of theoretical investigation of the equilibrium spatial configuration, electronic structure, and optical properties of the Zn‐based metal–organic framework [{Zn2(TBAPy)(H2O)2}*3.5DEF]n are reported. The electronic structure is obtained in frameworks of the density‐functional theory (DFT) with BLYP and PBE exchange‐correlation functionals, and optical response is computed using time‐dependent density functional theory (TDDFT). It is shown that the formation of narrow LUMO and HOMO bands is provided by conjugated π‐electrons of the aromatic rings of the ligand. These bands have nontrivial pattern and contain regions of hyperbolic dispersion corresponding to highly anisotropic heavy fermions. Optical transitions between these bands result in the appearance of near‐threshold peaks in photoabsorption spectra. The structure of the bands prevents formation of the bright exciton states in the system, and thus optical response is governed by single particle excitations only.