Li 4 EPc : A metallo‐organic electride comprising metal‐nitrogen bonds

Abstract

An in silico design of a new metallo-organic electride, containing metal-nitrogen bonds, namely, Li4EPc, with high non-linear optical (NLO) properties (βtotal = 6.382 × 104 au) is presented. Density functional theory (DFT)-based computation has revealed the thermodynamic stability of Li42+ cluster encapsulated in EPc host moiety where EPc is an extended phthalocyanine system. Natural bond orbital (NBO) analysis is performed to study the bonding nature of the aforementioned species. We have also performed atoms in molecules (AIM) analysis to confirm the presence of an isolated electron at the interstitial tetrahedral hollow formed by three-dimensional Li42+ cluster attached with EPc ligand. Linear and NLO properties of the designed electride have been analyzed by polarizability (urn:x-wiley:00207608:media:qua26856:qua26856-math-0001) and first hyperpolarizability calculations (βtotal). Frequency dependent first hyperpolarizability, second harmonic generation (SHG), electro-optic Pockel's effect (EOPE) have also been computed. Furthermore, we report the hydrogen adsorption potential of each Li atom in Li4EPc system. The result shows that two H2 molecules can be adsorbed per lithium atom leading to a total of eight H2 molecules adsorbed by Li42+ cluster through physisorption process. This work provides a new insight into designing a stable metallo-organic electride (Li4EPc) with high NLO response which also can be used as an efficient hydrogen storage material.