La@[La 5 &B 30 ] 0/-/2- : endohedral trihedral metallo-borospherenes with spherical aromaticity.

It is well-known that transition-metal-doping induces dramatic changes in the structures and bonding of small boron clusters, as demonstrated by the newly observed perfect inverse sandwich D 8h [La(η 8 -B 8 )La] and D 9h [La(η 9 -B 9 )La] - . Based on extensive global minimum searches and first-principles theory calculations, we predict herein the possibility of perfect endohedral trihedral metallo-borospherene D 3h La@[La 5 &B 30 ] (1, 3 A' 1 ) and its monoanion C s La@[La 5 &B 30 ] - (2, 2 A') and dianion D 3h La@[La 5 &B 30 ] 2- (3, 1 A' 1 ). These La-doped boron clusters are composed of three inverse sandwich La(η 8 -B 8 )La on the waist and two inverse sandwich La(η 9 -B 9 )La on the top and bottom which share one apex La atom at the center and six periphery B 2 units between neighboring η 8 -B 8 and η 9 -B 9 rings, with three octo-coordinate La atoms and two nona-coordinate La atoms as integrated parts of the cage surface. Detailed adaptive natural density partitioning (AdNDP) and iso-chemical shielding surface (ICSS) analyses indicate that La@[La 5 &B 30 ] 0/-/2- (1/2/3) are spherically aromatic in nature. The one-dimensional nanowire La 4 B 21 (4, P 31 m ) constructed from D 3h La@[La 5 &B 30 ] (1) along the C 3 axis of the system appears to be metallic. The IR and Raman spectra of La@[La 5 &B 30 ] (1) and photoelectron spectroscopy of the slightly distorted C s La@[La 5 &B 30 ] - (2) are theoretically simulated to facilitate their spectroscopic characterizations.