Theoretical Study of the Substituent Effects on the Nonlinear Optical Properties of a Room‐Temperature‐Stable Organic Electride

Abstract

Excess-electron compounds can be considered as novel candidates for nonlinear optical (NLO) materials because of their large static first hyperpolarizabilities (β ). A room-temperature-stable, excess-electron compound, that is, the organic electride Na@(TriPip222), was successfully synthesized by the Dye group (J. Am. Chem. Soc. 2005, 127, 12416). In this work, the β of this electride was first evaluated to be 1.13×10 au, which revealed its potential as a high-performance NLO material. In particular, the substituent effects of different substituents on the structure, electride character, and NLO response of this electride were systemically studied for the first time by density functional theory calculations. The results revealed that the β of Na@(TriPip222) could be further increased to 8.30×10 au by introducing a fluoro substituent, whereas its NLO response completely disappeared if one nitryl group was introduced because the nitro-group substitution deprived the material of its electride identity. Moreover, herein the dependence of the NLO properties on the number of substituents and their relative positions was also detected in multifluoro-substituted Na@(TriPip222) compounds.

A Complex Containing Four Magnesium Atoms and Two Mg–Mg Bonds Behaving as an Electride

“…Due to the presence of loosely bound electrons, electrides exhibit some extraordinary properties, viz., high non‐linear optical (NLO) behavior,, electron‐emitting, superconductivity, high reducing ability, even they can act as reversible hydrogen storage material and can activate small molecules , . But the extent of these properties depend on the sensitivity towards heat and air and thus on the stability of these electrides . Thus modeling and synthesis of temperature and air‐stable electrides are always demanding.…”

Electronic and vibrational hyperpolarizabilities of alkali‐ and alkaline‐earth‐doped boron nitride nanotubes

“…[8] A number of organic (and inorganic) systems with electride characteristic have been designed: complexants, clusters, nanocages, and nanotubes. [6,7,[17][18][19][20][21][22][23] Karamanis and Pouchan, [24] for instance, investigated the functionalization of graphene nanoribbons and flakes with lithium atoms, obtaining a remarkable increase in the hyperpolarizability for small size structures. Garcia-Borras et al [25] studied the electronic and vibrational NLO properties of five representative electrides: Li@Calix, Na@Calix, Li@B 10 H 14 , Li •+ 2 TCNQ •− , and NA •+ 2 TCNQ •− verifying that the vibrational NLO properties of the electrides are a result of both the diffuse electron distribution and the location of the excess electron density at a nonspecific atomic site.…”

“…On the basis of the previous works on the electron‐solvated systems, in‐depth studies of new NLO materials have focused on the compounds with loosely bound excess electrons . A number of organic (and inorganic) systems with electride characteristic have been designed: complexants, clusters, nanocages, and nanotubes . Karamanis and Pouchan, for instance, investigated the functionalization of graphene nanoribbons and flakes with lithium atoms, obtaining a remarkable increase in the hyperpolarizability for small size structures.…”

Activation of Small Molecules (H2, CO2, N2O, CH4, and C6H6) by a Porphyrinoid-Based Dimagnesium(I) Complex, an Electride

“…30 The stability and hence the practical applications of electrides depend on their sensitivity toward air and temperature. 31…”