Nan@Tetracyanoethylene (n=1-4) systems: Sodium salt vs Sodium electride

Abstract

Electrides are interesting and promising materials with cavity-trapped electrons which can be used as source of electron donor in different systems. Hereby, we have explored the possible formation of electride materials based on tetracyanoethylene (TCNE) backbone at MP2 computational level. This is achieved by systematic addition of up to four Na atoms to TCNE backbone. Our results predict high thermodynamic stability in the Nan@TCNE (n=1-4) systems. Moreover, based on the evaluation of four criteria, non-nuclear attractor (NNA), electron localization function (ELF), electron density laplacian (∇^2 ρ(r)), and non-linear optical (NLO), TCNE-Na1 and TCNE-Na2 and TCNE-Na4 species are conventional donor-acceptor systems (lithium salt). In contrast, the TCNE-Na3 species can be introduced as sodium electride with cavity-trapped electrons. Therefore, Na:TCNE ratio is very significant factor to provide species with electride feature through the addition of Na atoms to TCNE backbone.

Keywords

• tetracyanoethylene
• sodium salt
• sodium electride
• confined electron