Endohedral Ca@B38 stabilization of a B38

    Based on extensive global-minimum searches and first-principles electronic structure calculations, we present the viability of an endohedral metalloborospherene Cs Ca@B38 (1) which contains a Cs B382 (2) dianion composed of interwoven boron double chains with a r + p double delocalization bonding pattern, extending the Bn q (q = n  40) borospherene family from n = 39–42 to n = 38. Transition metal endohedral complexes Cs M@B38 (M = Sc, Y, Ti) (3, 5, 7) based on Cs B382 (2) are also predicted.