ISSN:
0044-2313
Keywords:
Ternary halides
;
synthesis
;
crystal structures
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Synthesis and Crystal Structures of the Ternary Rare Earth Chlorides NaMCl4 (M = Eu - Yb, Y)Single crystals of NaErCl4 were obtained from the melt of NaCl and ErCl3 (1:1 molar ratio) by slow cooling. It crystallizes in the monoclinic crystal system (space group P2/c) with the structure of α-NiWO4 with a = 632.24(9) pm, b = 759.78(9) pm, c = 674.2(1) pm, b̃ = 92.310(3)°, Z = 2. Two preparative routes to pure powder samples of the chlorides NaMCl4 are described. At room temperature, these are found to be isotypic with NaErCl4 (M = Tm - Yb; II) while the triclinic structure of NaGdCl4 is adopted with M = Gd - Ho, Y (I). Phase transitions from one structure to the other are observed for all compounds. The transition temperatures decrease with decreasing size of the ion M3+.
Notes:
Einkristalle von NaErCl4 erhält man durch langsames Abkühlen einer Schmelze von NaCl und ErCl3 (molares Verhältnis 1:1). NaErCl4-II kristallisiert monoklin (Raumgruppe P2/c) im α-NiWO4-Typ mit a = 632,24(9) pm, b = 759,78(9) pm, c = 674,2(1) pm, b̃ = 92,310(3)°, Z = 2. Zwei Wege zu reinen Pulverproben der Chloride NaMCl4 werden beschrieben. Bei Raumtemperatur sind diese für M = Tm - Yb isotyp zu NaErCl4 (II), mit M = Gd - Ho, Y kristallisieren sie in der triklinen Struktur von NaGdCl4 (I). Beide Modifikationen lassen sich reversibel ineinander umwandeln. Die Umwandlungstemperaturen werden mit abnehmendem Ionenradius von M3+ kleiner.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/zaac.19956210408
