Boron bond lengths

The boron-boron bond lengths, 180 pm, are 18 pm greater than the single-bond value, 162 pm we may say that in tetragonal boron each atom with ligancy 6 uses its three electrons to form six half-bonds, rather than three electron-pair bonds. 

Hexaborides of a CaBg type are formed by K, the alkaline earths, Y and the larger lanthanides, as well as Th and some actinides ". The crystal structure of these compounds with cubic symmetry (Pm3m, O, ) (see Fig. 1) is characterized by a three-dimensional skeleton of Bg boron octahedra, the interstices of which are filled by metal atoms. The connection between two octahedra is by a B—B bond of length 1.66 X 10 pm, whereas the B—B bond lengths in one octahedron are 1.76 X 10 pm. ... 

C21-0097. Construct a table of bond lengths that supports the existence of 7r bonding in boron trifluoride and boric acid. The relevant data can be found in the text. Label your table thoroughly. 

When applying these methods to the study of molybdenum complexes Voityuk and Rosch [25, 41] found that the use of the AMI core-repulsion function (Eq. 5-6) led to some systematic deviations for some Mo—X bond lengths. To address these problems, important changes to the core-repulsion function were made by the introduction of bond-specific parameters (omo-x and 8 io-x, Eq. 5-9) [22, 25], The idea of using bond-specific core repulsion parameters is not new, since the AMI parameterisation of boron used bond-specific Gaussian functions to improve the final results [42],... 

Table 8.4 Bond Length and Coordination Number in the Chlorides, Fluorides, and Hydrides of Boron and Carbon...

Boraadamantane donor-acceptor complexes, owing to their rigid framework, present a particular interest allowing the influence of steric factors on the bond length between the boron and donor atom to be revealed. Up to now c. 15... 

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