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Crystal Structure of Praseodymium Carbide Iodide,[Pr14 (C2) 3]

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Crystal Structure of Praseodymium Carbide Iodide,[Pr14 (C2) 3] Z. Kristallogr. NCS 222 (2007) 9-10 / DOI 10.1524/ncrs.2007.0004 9 © by Oldenbourg Wissenschaftsverlag, München Crystal structure of praseodymium carbide iodide, [Pr14(C2)3]I20 Rafa» Wiglusz, Ingo Pantenburg and Gerd Meyer* Universität zu Köln, Institut für Anorganische Chemie, Greinstraße 6, 50939 Köln, Germany Received December 15, 2006, accepted and available on-line March 29, 2007; CSD no. 409907 Abstract Source of material C3I10Pr7, triclinic, P1 (no. 2), a = 9.604(2) Å, PrI3 was synthesized from the elements and purified by high- a b = 11.577(2) Å, c = 13.796(2) Å, = 80.05(1)°, vacuum sublimation [1]. A mixture of PrI3, Pr and C in a molar ra- 3 b = 71.87(1)°, g = 65.89(1)°, V = 1328.7 Å , Z =2, tio 1.11:1.22:1 was filled under dry-box conditions (MBraun, 2 Rgt(F) = 0.050, wRref(F ) = 0.145, T =170K. Garching, argon atmosphere) into a tantalum tube which was he- _____________ lium-arc welded and jacketed in a silica tube under reduced pres- * Correspondence author (e-mail: [email protected]) sure. The sample was heated to 1000 K, kept there for two weeks, 10 [Pr14(C2)3]I20 cooled with 10 K/h to 800 K, annealed there for another two analogues of lanthanum and cerium, oligomers of three [Pr6(C2)] weeks and finally cooled to ambient temperature with 20 K/h. octahedra sharing two common trans edges, [Pr14(C2)3]I24, which Black single crystals of [Pr14(C2)3]I20 were selected with the aid are further connected via a-i bridges with other such oligomers, of a microscope in an argon-filled dry-box and mounted in thin- see for a detailed description of the structure [8]. For [M14(C2)3]I20, walled glass capillaries. subject to the phenomenon of the lanthanide contraction, the vol- umes of the unit cells decrease from 1396.5 Å3 (M = La), via Experimental details 1364.1 Å3 (M = Ce), both values from [8], to 1328.7 Å3 (M = Pr). The somewhat inaccurate displacement parameters of the C atoms The analogous pattern is seen for the individual distances MM are due to the small disorder of the atoms of the intercalated C2 (3.95 Å, 3.93 Å, 3.87 Å), MI (3.30 Å, 3.26 Å, 3.24 Å), and molecules. MC (2.68 Å, 2.66 Å, 2.65 Å) (M = La, Ce, Pr). Discussion Table 1. Data collection and handling. Except for the binary iodides of praseodymium, Pr2I5 [2] and PrI2 [3,4], there are also such with praseodymium octahedra stabilized with interstitial mono- or di-carbon or transition metal atoms, for Crystal: black column, size 0.1 × 0.1 × 0.4 mm Wavelength: Mo Ka radiation (0.71073 Å) − example Pr[Pr6(C)]I12 [5] and the isostructural Pr[Pr6(Fe)]I12 [6] m: 241.79 cm 1 as well as Pr12(C2)I17 [7]. These contain either isolated or edge- Diffractometer, scan mode: Stoe IPDS II, w/j q sharing [Pr6(Z)] octahedra. We have now also obtained the oligo- 2 max: 59.16° meric [Pr (C ) ]I . This compound is isostructural with the re- N(hkl)measured, N(hkl)unique: 18051, 7320 14 2 3 20 Criterion for I , N(hkl) : I >2s(I ), 3806 cently observed analogous iodides of lanthanum and cerium, obs gt obs obs N(param)refined: 182 [M14(C2)3]I20 (M = La, Ce) [8]. Programs: SIR92 [9], SHELXL-97 [10] The crystal structure of [Pr14(C2)3]I20 contains, as the isostructural 2 Table 2. Atomic coordinates and displacement parameters (in Å ). Atom Site xyzU11 U22 U33 U12 U13 U23 Pr(1) 2i 0.0499(1) 0.8837(1) 0.17646(8) 0.0191(5) 0.0179(5) 0.0193(5) −0.0070(4) −0.0060(4) −0.0022(4) Pr(2) 2i −0.1691(1) 0.2461(1) 0.10134(8) 0.0182(5) 0.0180(5) 0.0177(5) −0.0082(4) −0.0041(4) −0.0017(4) Pr(3) 2i −0.2557(1) 0.9507(1) 0.07958(8) 0.0173(5) 0.0195(5) 0.0220(5) −0.0079(4) −0.0054(4) −0.0038(4) Pr(4) 2i −0.3762(1) 0.0731(1) 0.35874(8) 0.0215(5) 0.0324(6) 0.0207(5) −0.0151(5) −0.0076(4) 0.0053(4) Pr(5) 2i −0.0461(1) 0.5789(1) 0.16507(8) 0.0220(5) 0.0322(6) 0.0206(5) −0.0157(5) −0.0065(4) 0.0031(4) Pr(6) 2i −0.1320(1) 0.7211(1) 0.41555(8) 0.0188(5) 0.0196(5) 0.0209(5) −0.0081(4) −0.0039(4) −0.0032(4) Pr(7) 2i −0.4617(1) 0.7925(1) 0.30887(8) 0.0193(5) 0.0198(5) 0.0191(5) −0.0076(4) −0.0061(4) −0.0015(4) I(1) 2i −0.7151(1) 0.0471(1) 0.43072(9) 0.0171(6) 0.0206(6) 0.0178(5) −0.0080(5) −0.0037(4) −0.0022(4) I(2) 2i 0.1464(2) 0.3059(1) 0.04332(9) 0.0197(6) 0.0235(6) 0.0194(6) −0.0108(5) −0.0058(4) −0.0008(5) I(3) 2i 0.2852(1) 0.6038(1) 0.09124(9) 0.0174(5) 0.0202(6) 0.0195(6) −0.0075(5) −0.0048(4) −0.0003(5) I(4) 2i −0.0686(2) 0.1335(1) 0.30564(9) 0.0209(6) 0.0211(6) 0.0180(5) −0.0106(5) −0.0058(4) −0.0007(4) I(5) 2i −0.3551(2) 0.5205(1) 0.2238(1) 0.0198(6) 0.0200(6) 0.0267(6) −0.0097(5) −0.0031(5) −0.0045(5) I(6) 2i 0.3962(2) 0.9217(2) 0.1217(1) 0.0219(5) 0.0314(7) 0.0219(6) −0.0145(5) −0.0085(4) 0.0045(5) I(7) 2i −0.1906(2) 0.2487(1) 0.6242(1) 0.0220(6) 0.0275(7) 0.0216(6) −0.0118(5) −0.0079(5) 0.0022(5) I(8) 2i −0.5637(2) 0.3458(1) 0.4759(1) 0.0228(6) 0.0285(7) 0.0219(6) −0.0132(5) −0.0062(5) 0.0046(5) I(9) 2i 0.0438(2) 0.4297(1) 0.3620(1) 0.0293(6) 0.0190(6) 0.0225(6) −0.0070(5) −0.0086(5) −0.0010(5) I(10) 2i −0.5011(1) 0.2229(1) 0.17015(9) 0.0177(6) 0.0199(6) 0.0193(6) −0.0083(5) −0.0041(4) 0.0004(4) C(1) 2i −0.031(2) 0.053(2) 0.021(1) 0.016(8) 0.03(1) 0.015(8) −0.009(8) −0.006(7) 0.015(7) C(2) 2i −0.242(2) 0.884(2) 0.276(2) 0.014(8) 0.010(8) 0.03(1) −0.006(6) −0.002(7) −0.004(7) C(3) 2i −0.171(2) 0.779(2) 0.232(2) 0.013(8) 0.03(1) 0.03(1) −0.017(8) −0.008(7) 0.016(8) Acknowledgments. This work was supported generously by the Deutsche Forschungsgemeinschaft (DFG, Bonn) within the framework of the Sonder- forschungsbereich Komplexe Übergangsmetallverbindungen mit Spin- und Ladungsfreiheitsgraden und Unordnung (SFB 608). 5. Simon, A.; Mattausch, H. J.; Bauhofer, W.; Kremer, R. K.: Metal-Rich Halides. In: Handbook on the Physics and Chemistry of Rare Earths References (Eds. K. A. Gschneidner Jr., L. Eyring), p. 191-285. Elsevier Science, Amsterdam 1991. 1. Meyer, G.: Binary Lanthanide(III) Halides, MX3 (X = Cl, Br, I). In: Synthe- 6. Palasyuk, A.; Pantenburg, I.; Meyer, G.: Praseodymium dodecaiodo- sis of Lanthanide and Actinide Compounds (Eds. G. Meyer, L. R. Morss), ferro-octahedro-hexapraseodymium, Pr7I12Fe. Acta Crystallogr. E62 p. 135-144. Kluwer Acad. Publ., Dordrecht NL (1991). (2006) i61-i62. 2. Krämer, K.; Meyer, G.; Fischer, P.; Hewat, A.; Güdel, H. U.: Magnetic 7. Uhrlandt, S.; Meyer, G.: Crystal structure of praseodymium carbide io- Phase Transitions to Long-Range Antiferromagnetic Ordering in the dide, [Pr12(C2)3]I17. Z. Kristallogr. 210 (1995) 361. Free-Electron Praseodym Halides Pr2X5 (X = Br, I). J. Solid State Chem. 8. Mattausch, H. J.; Simon, A.; Kienle, L.; Hoch, C.; Zheng, C.; Kremer, R. 95 (1991) 1-13. K.: EYPHKAMEN: Ln-Oktaedertripel in Ln14(C2)3I20 mit Ln = La, Ce. 3. Gerlitzki, N.; Meyer, G.; Mudring, A.-V.; Corbett, J. D.: Praseodymium Z. Anorg. Allg. Chem. 632 (2006) 1661-1670. diiodide, PrI2, revisited by synthesis, structure determination and theory. 9. Altomare, A.; Cascarano, M.; Giacovazzo, C.; Guagliardi, A.; Burla, M. J. Alloys Compd. 380 (2004) 211-218. C.; Polidori, G.; Carnalli, M.: SIR92 a program for automatic solution of 4. Meyer, G.; Palasyuk, A.: Forty-five Years of Praseodymium Di-iodide. crystal structure by direct methods. J. Appl. Crystallogr. 27 (1994) 435. In: Inorganic Chemistry in Focus (Eds. G. Meyer, D. Naumann, L. 10. Sheldrick, G. M.: SHELXL-97. Program for the Refinement of Crystal Wesemann), p. 45-60. Wiley-VCH, Weinheim 2006. Structures. University of Göttingen, Germany 1997..
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