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A hydrogen molecular ion cluster or hydrogen cluster ion is a positively charged cluster of hydrogen molecules. The hydrogen molecular ion (H2+) and trihydrogen ion (H3+) are well defined molecular species. However hydrogen also forms singly charged clusters (Hn+) with n up to 120. ==Experiments== Hydrogen ion clusters can be formed in liquid helium or with lesser cluster size in pure hydrogen. H6+ is far more common than higher even numbered clusters. H6+ is stable in solid hydrogen. The positive charge is balanced by a solvated electron. It is formed when ionizing radiation impinges on solid hydrogen, and so is formed in radioactive solid tritium. In natural hydrogen treated with radiation, the positive charge transfers to HD molecules, in preference to H2, with the ultimate most stable arrangement being HD(HD)+HD. H6+ can migrate though solid hydrogen by linking a hydrogen molecule at one end and losing it at the other: H2 + H6+ → H6+ + H2. This migration stops once an HD molecule is added resulting in a lower energy level. HD or D2 is added in preference over H2. Clampitt and Gowland found clusters with an odd number of hydrogen atoms H3+2n+ and later showed that H15+ was relatively stable. H3+ formed the core of this cluster with six H2 molecules surrounding it. Hiroka studied the stability of the odd numbered clusters in gas up to H21+. Bae determined that H15+ was especially stable amongst the odd numbered clusters.〔 Kirchner discovered even numbered atomic clusters in gas at lower concentrations than the odd numbered atom clusters. H6+ was twenty times less abundant than H5+. H4+ H8+ and H10+ were detected at lesser amounts than H6+. Kurosaki and Takayanagi showed that H6+ is much more stable than other even clusters and showed antiprismatic symmetry of order 4 (D2d molecular symmetry). This turnstyle structured molecule was computationally found to be more energetically stable than a ring of five hydrogen atoms around a proton. Negative hydrogen clusters have not been found to exist. H3− is theoretically unstable, but D3− in theory is bound at 0.003 eV.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hydrogen ion cluster」の詳細全文を読む スポンサード リンク
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