Encapsulation of Small Base Molecules and Tetrahedral/Cubane-Like Clusters of Group V Atoms in the Boron Buckyball: A Density Functional Theory Study

Abstract

A density functional theory study of small base molecules and tetrahedral and cubane-like group V clusters encapsulated in B(80) shows that the boron buckyball is a hard acid and prefers hard bases like NH(3) or N(2)H(4) to form stable off-centered complexes. In contrast, tetrahedral and cubane-like clusters of this family are metastable in the cage. The most favorable clusters are the mixed tetrahedral and cubane clusters formed by nitrogen and phosphorus atoms such as P(2)N(2)@B(80), P(3)N@B(80), and P(4)N(4)@B(80). The boron cap atoms are electrophilic centers, and prefer mainly to react with electron rich nucleophilic sites. The stability of the complexes will be governed by the size and electron donating character of the encapsulated clusters. B(80) forms stable complexes with hard materials where a bidentate interaction of the encapsulated molecule with two boron cap atoms is preferred over a single direct complex toward a single endohedral boron.

Ring currents in boron and carbon buckyballs, B80 and C60

“…15 A recent study even claims that there may not be driving forces towards well defined structures, and that the potential energy surface of the larger boron clusters resembles a glasslike landscape. 16,17 In view of its high symmetry and its paradigmatic electronic structure, the boron buckyball continues to attract detailed theoretical studies of its chemical and physical properties, [18][19][20][21][22] as was the case for its famous carbon congener in previous decades. In the present work we calculate the magnetically induced ring currents in the boron buckyball, both in I h and T h symmetries, and compare them with those of C 60 .…”

A theoretical study on the stability difference of the borane BnHn2− and carborane C2Bn−2Hn(5 ≤ n ≤ 7) clusters

“…By the way, it should be mentioned that the relative stability of various isomers of carborane C 2 B n −2 H n (5 ≤ n ≤ 7) had ever been studied by Williams, Jemmis, Gimarc, and McKee . The geometries of (5 ≤ n ≤ 7), 1,5‐C 2 B 3 H 5 , 1,6‐C 2 B 4 H 6 , and 1,7‐C 2 B 5 H 7 displayed in Figure are optimized and confirmed by vibration frequency analysis at B3LYP/def2‐TZVPP level with Gaussian 09 package, where the B3LYP/def2‐TZVPP method is always used as structure optimization method for boranes and borane analogs . Based on the geometry optimization results, the precise frontier orbital energy levels E SCF (∞) are extrapolated according to Eq.…”

The Boron Conundrum: Which Principles Underlie the Formation of Large Hollow Boron Cages?

“…Since the discovery of boron nanotubes and the tendency of small boron clusters to keep planar or quasi-planar shapes, it has been believed that large boron clusters may have fullerene-like structures. Several theoretical studies [16,[19][20][21][22][23][24][25][26][27][38][39][40][41][42][43][44][45][46] have been reported that characterise the leapfrog boron fullerene B 80 with all 20 hexagons capped. Wang [19] mentioned that the displacement of hexagon caps towards pentagons leads to more stable boron clusters, but could not give any reliable explanation for the relative stability of these structures.…”

“…The authors thank the KULeuven Research Council and the Flemish Science Fund (FWO-Vlaanderen) for financial support and P. W. Fowler for sending us the coordinates of the C 24 Keywords: boron · cage compounds · cluster compounds · density functional calculations · isomers…”

“…[22 ] A JT study on B 80 + revealed that the ground state of B 80 + contrarily to C 60 + distorts slightly from D 3d to S 6 . [23] The boron buckyball was found to be chemically more active than C 60 ; [24] it behaves as an amphoteric molecule and can retain some hydride molecules on its surface. [25] The current densities in B 80 were also found to be higher than in C 60 .…”