Crystal Structure and Magnetic Properties of a New Oxyselenide of Gadolinium and Titanium: Gd4TiSe4O4

✍ Scribed by A. Meerschaut; A. Lafond; V. Meignen; C. Deudon

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 452 KB
• Volume: 162
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.2001.9223

✦ Synopsis

IN HONOR OF PROFESSOR PAUL HAGENMULLER ON THE OCCASION OF HIS 80TH BIRTHDAY

A new compound Gd 4 TiSe 4 O 4 has been obtained by a solid state reaction of Gd 2 O 3 , TiO 2 , and TiSe 2 , at T ‫؍‬ 10003C, with the addition of iodine to favor crystallization. Single-crystal X-ray di4raction measurements show that Gd 4 TiSe 4 O 4 crystallizes in space group C2/m (No. 12) of the monoclinic system with two formula units in a cell of dimensions a ‫؍‬ 15.7878(4) A > , b ‫؍‬ 3.7610(2) A > , c ‫؍‬ 9.6639(3) A > , and ‫؍‬ 117.569(2)3. The structure contains two crystallographically independent Gd atoms with a bicapped trigonal prismatic coordination. Association of four adjacent Gd-centered polyhedra constitutes the elemental building unit, which develops into ribbons along b. The ribbons are interconnected by in5nite chains of edge-sharing Ti-centered octahedra. Magnetic susceptibility of the title compound has been measured from 1.8 to 300 K, and from B ‫؍‬ 1.10 ؊3 to 0.1 T for the ZFC and FC cooling modes. The linear variation of the inverse susceptibility versus T can be modeled with a Curie+Weiss law in agreement with a Gd 3؉ free ion behavior. The maximum of the (T) curve at about 2.5 K could be attributed to both an antiferromagnetic transition and the saturation of the weak ferromagnetic component.