The Stannides EuPd2Sn2, EuPt2Sn2, EuAu2Sn2, and Eu3Ag5.4Sn5.6 - Structure and Magnetic Properties

被引:13
作者
Schwickert, Christian [1 ]
Winter, Florian [1 ]
Poettgen, Rainer [1 ]
机构
[1] Univ Munster, Inst Anorgan & Analyt Chem, D-48149 Munster, Germany
来源
ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES | 2014年 / 69卷 / 07期
关键词
Europium; Stannides; Magnetic Properties; Sn-119 Mossbauer Spectroscopy; Eu-151 Mossbauer Spectroscopy; CRYSTAL-STRUCTURE; TRANSITION-METAL; COMPUTER-PROGRAM; ALKALINE-EARTHS; TERNARY PHASES; X-RAY; MOSSBAUER; EU; SN; SN-119;
D O I
10.5560/ZNB.2014-4098
中图分类号
O61 [无机化学];
学科分类号
070301 ; 081704 ;
摘要
The europium stannides EuT2Sn2 (T = Pd, Pt, Au) and Eu3Ag5.4Sn5.6 were synthesized by high-frequency melting of the elements in sealed niobium ampoules in a water-cooled sample chamber. All samples were characterized by powder X-ray diffraction. The EuT2Sn2 (T = Pd, Pt, Au) stannides crystallize with the CaBe2Ge2-type structure, space group P4/nmm. The structure of EuPd2Sn2 was refined from single-crystal X-ray diffractometer data: a = 462.44(8), c = 1045.8(3) pm, wR = = 0.0402, 237 F-2 values and 15 refined variables. The palladium and tin atoms build up a three-dimensional [Pd2Sn2] polyanionic network, exclusively with Pd-Sn interactions (261 269 pm). The Pd1 and Pd2 atoms have square-pyramidal and tetrahedral tin coordination, respectively. The europium atoms fill large voids within the network. They are coordinated to eight palladium and eight tin atoms. Temperature-dependent magnetic susceptibility studies confirm a stable divalent ground state of the europium atoms. The compounds become ordered antiferromagnetically below 6.3 (EuPd2Sn2), 6.1 (EuPt2Sn2) and 7.7 K (EuAu2Sn2). Eu3Ag5.4Sn5.6 adopts a partially ordered variant of the La(3)A(11) type, space group Imnim, a = 471.33(8), b = 1382.5(4), c = 1032.4(2) pm, wR = 0.0449, 692 F-2 values, 30 variables. The three-dimensional [Ag5.4Sn5.6] network shows one silver and one tin site besides two sites with substantial Ag/Sn mixing. The two crystallographically independent europium atoms fill larger and smaller cavities within the [Ag5.4Sn5.6] network. Eu3Ag5.4Sn5.6 also shows divalent europium and antiferromagnetic ordering at T-N = 6.9 K. A Eu-151 Mossbauer spectrum of Eu3Ag5.4Sn5.6 at 5.2 K shows an isomer shift of delta = 10.61 mm s(-1), typical for Eu(II) compounds, and a magnetic hyperfine field splitting of B-Hf = 5.9 T. Sn-119 Mossbauer spectra of the four stannides show isomer shifts in the range of delta = 1.78 - 2.20 mm s(-1), usually observed for tin in intermetallic compounds.
引用
收藏
页码:775 / 785
页数:11
相关论文
共 55 条
  • [1] MAGNETIC-SUSCEPTIBILITY AND ELECTRICAL-RESISTIVITY MEASUREMENTS ON RPDSN (R = CE-YB) COMPOUNDS
    ADROJA, DT
    MALIK, SK
    [J]. PHYSICAL REVIEW B, 1992, 45 (02) : 779 - 785
  • [2] Valence of Eu ion in Eu3Ir4Sn13 at low temperatures
    Aoki, Y
    Fukuhara, T
    Sugawara, H
    Sato, H
    [J]. JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 1996, 65 (04) : 1005 - 1009
  • [3] Brand R. A., 2007, NORMOS MOSSBAUER FIT
  • [5] DEMESQUITA AH, 1967, ACTA CRYSTALLOGR, V22, P497
  • [6] Crystal structure and magnetic ordering in dimorphic EuZn2Sn2
    Dhar, S. K.
    Paulose, P.
    Kulkarni, R.
    Manfrinetti, P.
    Pani, M.
    Parodi, N.
    [J]. SOLID STATE COMMUNICATIONS, 2009, 149 (1-2) : 68 - 72
  • [7] Donohue J., 1974, The Structures of the Elements
  • [8] Dormann JL, 1996, ITAL PHY SO, V50, P339
  • [9] EISENMAN.B, 1972, Z NATURFORSCH PT B, VB 27, P1155
  • [10] Emsley J., 1999, ELEMENTS