The structure and large nonlinear optical properties of a novel octupolar electride Li@36Adz

Based on the synthesized H@3(6)Adz (3(6)Adz = 3(6) adamanzane), a new class of three-dimensional (3D) octupolar molecule Li@3(6)Adz with electride characteristics is first designed and studied with theoretical tools, in which the electron of the encapsulated Li atom is extruded from the cage of 3(6)Adz forming diffused excess electron. Due to S-4 symmetry, Li@3(6)Adz only has the octupolar hyperpolarizability (beta(j=3)) up to 1787 x 10(-30) esu at the restricted open-shell second-order Moller-Plesset (ROMP2) level, whose beta is about 1787 times more than that (1 x 10(-30) esu) of its analogue (H@3(6)Adz). Interestingly, we find that both Li@3(6)Adz has a very low ionization potential (1.84 eV) which can be seen as superalkalies. The present investigations will enrich the concept of 3D octupolar molecules for high-performance NLO materials and offer a method to construct superalkalies. (C) 2013 Elsevier B.V. All rights reserved.