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The Pearson symbol, or Pearson notation, is used in crystallography as a means of describing a crystal structure, and was originated by W.B. Pearson.〔W.B. Pearson, A Handbook of Lattice Spacings and Structures of Metals and Alloys,Vol. 2, Pergamon Press, Oxford, 1967〕 The symbol is made up of two letters followed by a number. For example: * Diamond structure, ''cF''8 * Rutile structure, ''tP''6 The two (italicised) letters specify the Bravais lattice. The lower case letter specifies the crystal class, and the upper case letter the lattice type. The figure gives the number of the atoms in the unit cell. IUPAC (2005) 〔(Nomenclature of Inorganic Chemistry IUPAC Recommendations 2005 ); IR-3.4.4, pp.49-51; IR-11.5, pp.241-242〕 The letters A, B and C were formerly used instead of S. When the centering had a pair of opposite faces along the X-axis, it was called A-centered. Equivalent centering along the Y- and Z-axes were called B- and C-centered, respectively.〔 The fourteen possible Bravais lattices are identified by the first two letters: ==Pearson symbol and space group== The Pearson symbol does not uniquely identify the space group of a crystal structure, for example both the NaCl structure, (space group Fmm) and diamond (space group Fdm) have the same Pearson symbol ''cF''8. 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「Pearson symbol」の詳細全文を読む スポンサード リンク
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