Stannide

{{Short description|Intermetallic compound made with tin and other metals}} A '''stannide''' can refer to an intermetallic compound containing tin combined with one or more other metals; an anion consisting solely of tin atoms or a compound containing such an anion, or, in the field of organometallic chemistry an ionic compound containing an organotin anion<ref>{{cite journal | last1 = Flacke | first1 = F. | last2 = Jacobs | first2 = H. | year = 1997 | title = [Li(NH₃)₄] [Sn(SnPh₃)₃].C₆H₆, Crystal structure of a stannide with trigonal pyramidal tin skeleton | journal = European Journal of Solid State and Inorganic Chemistry | volume = 34 | issue = 5| pages = 495–501 }}</ref>. An alternative name for such a compound is stannanide.

==Binary alkali and alkaline earth stannides== When tin is combined with an alkali or alkaline earth metal some of the compounds formed have ionic structures containing monatomic or polyatomic tin anions (Zintl ions), such as Sn⁴⁻ in Mg₂Sn<ref name = "Kauzlarich">S.M. Kauzlarich,(1994), Zintl Compounds, Encyclopedia of Inorganic Chemistry, John Wiley & sons, {{ISBN|0-471-93620-0}}</ref> or {{chem|Sn|9|4−}} in K₄Sn₉.<ref name = "Hoch">{{cite journal | last1 = Hoch | first1 = C. | last2 = Wendorff | first2 = M. | last3 = Röhr | first3 = C. | year = 2002 | title = Tetrapotassium nonastannide, K₄Sn₉ | journal = Acta Crystallogr C | volume = 58 | issue = 4| pages = i45–i46 | doi = 10.1107/S0108270102002032 | pmid = 11932511 | bibcode = 2002AcCrC..58I..45H }}</ref> Even with these metals not all of the compounds formed can be considered to be ionic with localised bonding, for example Sr₃Sn₅, a metallic compound, contains {Sn₅} square pyramidal units.<ref>{{cite journal | last1 = Klem | first1 = M. T. | last2 = Vaughey | first2 = J. T. | last3 = Harp | first3 = J G. | last4 = Corbett | first4 = J D. | year = 2001 | title = A₃Tt₅ Phases Sr₃Sn₅, Ba₃Pb₅, and La₃Sn₅. Structure and Bonding in a Series of Isotypic Metallic Compounds with Increased Electron Count and Their Comparison with the Nominal Zintl Phase La₃In₅ | journal = Inorg. Chem. | volume = 40 | issue = 27| pages = 7020–7026 | doi = 10.1021/ic010804v | pmid = 11754285 }}</ref>

==Ternary alkali and alkaline earth stannides== Ternary (where there is an alkali or alkaline earth metal, a transition metal as well as tin e.g. LiRh₃Sn₅<ref>{{cite journal | last1 = Sreeraj | first1 = P | last2 = Johrendt | first2 = D. | last3 = Müller | first3 = H. | last4 = Hoffmann | first4 = R.-D. | last5 = Wu | first5 = Zhiyun | last6 = Pöttgen | first6 = R. | year = 2005 | title = The stannide LiRh₃Sn₅: Synthesis, structure, and chemical bonding | journal = Zeitschrift für Naturforschung B | volume = 60 | issue = 9| pages = 933–939 | doi = 10.1515/znb-2005-0904 | s2cid = 197000256 | doi-access = free }}</ref> and MgRuSn₄<ref>{{cite journal | last1 = Schlüter | first1 = M. | last2 = Kunst | first2 = A. | last3 = Pöttgen | first3 = R. | year = 2002| title = The Ternary Stannides MgRuSn₄ and Mg_''x''Rh₃Sn_7−''x'' (''x'' = 0.98–1.55) | journal = Zeitschrift für anorganische und allgemeine Chemie | volume = 628 | issue = 12| pages = 2641–2646 | doi = 10.1002/1521-3749(200212)628:12<2641::aid-zaac2641>3.0.co;2-y}}</ref>) have been investigated.

==Other metal stannides== Binary (involving one other metal) and ternary (involving two other metals) intermetallic stannides have been investigated. Niobium stannide, Nb₃Sn is perhaps the best known superconducting tin intermetallics. This is more commonly called "niobium-tin".

There are multiple rare earth stannides, including with dysprosium and yttrium.

==Stannide ions, {{chem|Sn|''x''|''y''−}}== Some examples of stannide Zintl ions are listed below. Some of them contain 2-centre 2-electron bonds (2c-2e), others are "electron deficient" and bonding sometimes can be described using polyhedral skeletal electron pair theory (Wade's rules) where the number of valence electrons contributed by each tin atom is considered to be 2 (the s electrons do not contribute).<ref>{{Greenwood&Earnshaw}}</ref> There are some examples of silicide and plumbide ions with similar structures, for example tetrahedral {{chem|Si|4|4−}}, the chain anion (Si²⁻)_''n'', {{chem|Pb|4|4−}} and {{chem|Pb|9|4−}}.<ref name = "Kauzlarich"/><ref> {{cite journal | last = Yong | first = Li |author2=Stephan D. Hoffmann |author3=Thomas F. Fässler | title = A low-dimensional arrangement of [Pb₉]⁴⁻ clusters in [K(18-crown-6)]₂K₂Pb₉·(en)_1.5 | journal = Inorganica Chimica Acta | volume = 359 | issue = 15 | pages = 4774–4778 | publisher = Elsevier | date = 1 December 2006 | doi = 10.1016/j.ica.2006.04.017 }} </ref> *Sn⁴⁻ found for example in Mg₂Sn.<ref name = "Kauzlarich"/> *{{chem|Sn|4|4−}}, tetrahedral with 2c-2e bonds e.g. in CsSn.<ref name = "Kauzlarich"/> *{{chem|Sn|4|2−}}, tetrahedral ''closo''-cluster with 10 electrons (2''n'' + 2).<ref>{{cite journal | last1 = Critchlow | first1 = S. C. | last2 = Corbett | first2 = J. D. | year = 1981| title = Stable homopolyatomic anions: the tetrastannide (2–) and tetragermanide(2–) anions, {{chem|Sn|4|2−}} and {{chem|Ge|4|2−}} X-ray crystal structure of {{chem|[K+(crypt)]|2|Sn|4|2−}}. ethylenediamine | journal = J. Chem. Soc. Chem. Commun.| volume = 1981 | issue = 5| pages = 236–237 | doi = 10.1039/C39810000236 }}</ref> *(Sn²⁻)_''n'' zig-zag chain polymeric anion with 2c-2e bonds found for example in BaSn.<ref name = "Kauzlarich"/> *{{chem|Sn|5|2−}} ''closo''-cluster, 12 electrons (2''n'' + 2), (i.e. trigonal bipyramidal) in (2,2,2-crypt-Na)₂Sn₅.<ref>{{cite journal | last1 = Edwards | first1 = P. A. | last2 = Corbett | first2 = J. D. | year = 1977 | title = Stable homopolyatomic anions. Synthesis and crystal structures of salts containing the pentaplumbide(2−) and pentastannide(2−) anions | journal = Inorg. Chem. | volume = 16 | issue = 4| pages = 903–907 | doi = 10.1021/ic50170a036 }}</ref> *{{chem|(Sn|8|4−|)|''n''}} polymeric two-dimensional anion in NaSn₂.<ref>{{cite journal | last1 = Dubois | first1 = F. | last2 = Schreyer | first2 = M. | last3 = Fässler | first3 = T. F. | year = 2005 | title = NaSn₂: A Novel Binary Zintl Phase with 2D Polyanions of Realgar-Type Units [Sn₈]⁴⁻ | journal = Inorg. Chem. | volume = 44 | issue = 3| pages = 477–479 | doi = 10.1021/ic048770p | pmid = 15679372 }}</ref> *{{chem|Sn|9|4−}} ''nido''-cluster 22 electrons (2''n'' + 4), capped square antiprismatic with as per polyhedral skeletal electron pair theory, in the intermetallic K₄Sn₉,<ref name = "Hoch"/> and a distorted ion in the salt Na₄Sn₉·7&nbsp;en.<ref>{{cite journal | last1 = Diehl | first1 = L. | last2 = Khodadadeh | first2 = K. | last3 = Kummer | first3 = D. | last4 = Strähle | first4 = J. | year = 1976 | title = Anorganische Polyederverbindungen, III. Zintl's Polyanionige Salze: Darstellung und Eigenschaften der kristallinen Verbindungen [Na₄·7 en]Sn₉, [Na₄·5 en]Ge₉ und [Na₃·4 en]Sb₇ und ihrer Lösungen Die Kristallstruktur von [Na₄·7 en]Sn₉ | journal = Chemische Berichte | volume = 109 | issue = 100| pages = 3404–3418 | doi = 10.1002/cber.19761091018 }}</ref> *{{chem|Sn|9|3−}} a paramagnetic, 21 electrons, ''closo''- cluster anion (D_3h symmetry), 1 more electron than the 20 (2''n'' + 2) predicted by polyhedral skeletal electron pair theory.<ref>{{cite journal | last1 = Critchlow | first1 = S. C. | last2 = Corbett | first2 = J. D. | year = 1983 | title = Homopolyatomic anions. The synthesis and characterization of the novel paramagnetic nonastannide(3−) anion {{chem|Sn|9|3−}}, a D_3h cluster with 21 skeletal electrons | journal = J. Am. Chem. Soc. | volume = 105 | issue = 17| pages = 5715–5716 | doi = 10.1021/ja00355a045 }}</ref> *{{chem|(Sn|12|7−|)|''n''}} polymeric two-dimensional anion in Na₇Sn₁₂<ref>.{{cite journal | last1 = Fässler | first1 = T.F. | last2 = Hoffmann | first2 = S. | year = 2003 | title = Na₇Sn₁₂: A Binary Zintl Phase with a Two-Dimensional Covalently Bonded Tin Framework | journal = Inorg. Chem. | volume = 42 | issue = 18| pages = 5474–5476 | doi = 10.1021/ic030148u | pmid = 12950190 }}</ref>

==References== {{reflist|30em}}

{{Monatomic anion compounds}}

Category:Tin Category:Intermetallics Category:Anions Category:Cluster chemistry