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In inorganic chemistry, a Nowotny chimney ladder phase (NCL phase) is a particular intermetallic crystal structure found with certain binary compounds. NLC phases are generally tetragonal and are composed of two separate sublattices. The first is a tetragonal array of transition metal atoms, generally from group 4 through group 9 of the periodic table. Contained within this array of transition metal atoms is a second network of main group atoms, typically from group 13 (boron group) or group 14 (carbon group). The transition metal atoms form a chimney with helical zigzag chain. The main-group elements form a ladder spiraling around the transition metal helix. The phase is named after one of the early investigators H. Nowotny.〔''Die Kristallstruktur von Mn11Si19 und deren Zusammenhang mit Disilicid-Typen'' O. Schwomma, A. Preisinger, H. Nowotny and A. Wittmann Monatshefte für Chemie / Chemical Monthly, 1964, Volume 95, Number 6, Pages 1527–1537 〕〔''Untersuchungen im System: Ru−Sn'' O. Schwomma, H. Nowotny and A. Wittmann Monatshefte für Chemie / Chemical Monthly Volume 95, Number 6, 1538–1543, 〕〔''Untersuchungen an Germaniden der Übergangsmetalle V, Cr, Mo und Mn'' H. Völlenkle, A. Wittmann and H. Nowotny Monatshefte für Chemie / Chemical Monthly Volume 95, Number 6, 1544–1549, 〕 Examples are RuGa2, Mn4Si7, Ru2Ge3, Ir3Ga5, Ir4Ge5 V17Ge31, Cr11Ge19, Mn11Si19, Mn15Si26, Mo9Ge16, Mo13Ge23, Rh10Ga17, and Rh17Ge22.〔''RuGavSnw Nowotny Chimney Ladder Phases and the 14-Electron Rule Guoxin'' Lu, Stephen Leeb, Jianhua Lin, Liping You, Junliang Sun and Joshua Teal Schmidt Journal of Solid State Chemistry Volume 164, Issue 2, 1 March 2002, Pages 210–219 〕 In RuGa2 the ruthenium atoms in the chimney are separated by 329 pm. The gallium atoms spiral around the Ru chimney with a Ga–Ga intrahelix distance of 257 pm. The view perpendicular to the chimney axis is that of a hexagonal lattice with gallium atoms occupying the vertices and ruthenium atoms occupying the center. Each gallium atom bonds to 5 other gallium atoms forming a distorted trigonal bipyramid. The gallium atoms carry a positive charge and the ruthenium atoms have a formal charge of −2 (filled 4d shell).〔''The Relationship between the Nowotny Chimney Ladder'' Solid State Phases and Metal-Phosphorus Wheels R. BRUCE KING REV. CHIM. 58 Nr. 5 2007〕 In Ru2Sn3 the ruthenium atoms spiral around the tin inner helix. In two dimension the Ru atoms form a tetragonal lattice with the tin atoms appearing as triangular units in the Ru channels.〔''The Nowotny Chimney Ladder Phases: Following the cpseudo Clue toward an Explanation of the 14 Electron Rule'' Daniel C. Fredrickson, Stephen Lee, Roald Hoffmann, and Jianhua Lin Inorg. Chem., 2004, 43 (20), pp 6151–6158 〕 The occurrence of a LCP phase can be predicted by the so-called 14 electron rule. In it the total number of valence electrons per transition metal atom is 14.〔''The crystal structure of Rh17Ga22, an example of a new kind of electron compound'' W. Jeitschko and E. Parthé Acta Cryst. (1967). 22, 417–430 〕〔''Phases with Nowotny chimney-ladder structures considered as `electron' phases'' W. B. Pearson Acta Cryst. (1970). B26, 1044–1046 〕〔''The Nowotny Chimney Ladder Phases: Whence the 14 Electron Rule?'' Daniel C. Fredrickson, Stephen Lee, and Roald Hoffmann Inorg. Chem., 2004, 43 (20), pp 6159–6167 〕 ==References== 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「Nowotny phase」の詳細全文を読む スポンサード リンク
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