The development of the chemistry of boron hydrides led to new experimental techniques and theoretical concepts. Boron hydrides have been studied as potential fuels, for rockets.
Over the past several decades, the scope of boron hydride chemistry has grown to include cages containing atoms other than boron, such as carbon in the carboranes and metals in the metallaboranes, wherein one or more boron atoms are substituted by metal atoms.
Boranes are electron-deficient and pose a problem for conventional descriptions of covalent bonding that involves shared electron pairs. BH3 is a trigonal planar molecule (D3h molecular symmetry). Diborane has a hydrogen-bridged structure Lipscomb's methodology has largely been superseded by a molecular orbital approach, although it still affords insights. The results of this have been summarised in a simple but powerful rule, PSEPT, often known as Wade's rules, that can be used to predict the cluster type, closo-, nido-, etc. The power of this rule is its ease of use and general applicability to many different cluster types other than boranes. There are continuing efforts by theoretical chemists to improve the treatment of the bonding in boranes — an example is Stone's tensor surface harmonic treatment of cluster bonding. A recent development is four-center two-electron bond.
The base value of each unit of ranges between 15 and 55Ð per unit, with up to 2 units being found at any one time.
Presence on Mars: Very Rare
|Group 1 | Group 2 | Group 3 | Group 4 | Group 5 | Group 6|
|Group 4|| |Actininum | Areanetium | Borane | Carbon Tetrachloride | Dubnium | Dysprosium | Erbium | Europium | Ferrous Dixenate | |Gadollinium | Golgathium | Holmium | Holmium Sulfate | Iron Golgathide | Neodymium | Praseodymium | Promethium | |Protactinium | Rutherfordium | Samarium | Selenium Arsenide | Terbium | Thallium Titanide | Thulium | Uranium|