Structural and ¹²¹Sb Mössbauer Spectroscopic Investigations of the Antimonide Oxides REMnSbO (RE = La, Ce, Pr, Nd, Sm, Gd, Tb) and REZnSbO (RE = La, Ce, Pr)

Abstract

Heading: I. Schellenberg et al. . Quaternary Antimonide Oxides)) The quaternary antimonide oxides REMnSbO (RE = La, Ce, Pr, Nd, Sm, Gd, Tb) and REZnSbO (RE = La, Ce, Pr) were synthesized from the RESb monoantimonides and MnO, respectively ZnO, in sealed tubes at 1170 K. Single crystals were obtained from NaCl/KCl salt fluxes. The ZrCuSiAs type (space group P4/nmm) structures of LaMnSbO (a = 423.95(7), c = 955.5(27) pm, wR2 = 0.067, 247 F 2 ), CeMnSbO (a = 420.8(1), c = 950.7(1) pm, wR2 = 0.097, 250 F 2 ), SmMnSbO (a = 413.1(1), c = 942.3(1) pm, wR2 = 0.068, 330 F 2 ), LaZnSbO (a = 422.67(6), c = 953.8(2) pm, wR2 = 0.052, 259 F 2 ), and NdZnSbO (a = 415.9(1), c = 945.4(4) pm, wR2 = 0.109, 206 F 2 ) were refined from single crystal X-ray diffractometer data. The structures are composed of covalently bonded (RE 3+ O 2-) + and (T 2+ Sb 3-)layers with weak ionic-like interlayer interactions. The oxygen and transition metal atoms both have tetrahedral coordination within the layers. 121 Sb Mössbauer spectra of the REMnSbO and REZnSbO compounds show single antimony sites with isomer shifts close to -8 mm/s, in agreement with the antimonide character of these samples. PrMnSbO and NdMnSbO show transferred hyperfine fields of 8 T at 4.2 K.

Structure and magnetic properties ofLnMnSbO(Ln=Laand Ce)

“…Figure 1 shows neutron powder diffraction scans of LaMnSbO and of CeMnSbO measured on HB1A above their AFM transition temperatures. The solid lines are best calculated intensities based on the ZrCuSiAs-type P 4/nmm space group consistent with previous powder x-ray diffraction reports 20 (note that the measurement and refinement include peaks from an Al sample can). The refinement of the CeMnSbO indicates that there is a small amount of MnSb present in the sample as an impurity phase.…”

“…The synthesis of the polycrystalline LaMnSbO compound is similar to that reported by Schellenberge et al 20 . Two starting materials MnO and LaSb were mixed thoroughly in stoichiometric proportions (LaSb was prepared firstly by reacting La and Sb powders at 600 o C for 5 h and subsequently at 950 o C for 12 h under 1/3 atm.…”

“…Room temperature structures of these two compounds have been reported 20 . Although both systems are expected to exhibit similar properties in the MnSb triple-plane, the presence of Ce or other magnetic rare-earth element has been shown to have an effect on the nuclear structure and the magnetic structure of the transition metal 12,14,15,19 .…”

Short- and long-range magnetic order in LaMnAsO

“…Arsenic can be replaced by antimony in the case of LnMnSbO and LnZnSbO [7], or by phosphorus, producing low temperature superconductors LnFePO with anisotropic gap structures [8,9]. Oxygen can be fully replaced by fluorine to form compounds like AFeAsF (A 2+ = Ca, Sr), whose properties are quite similar to those of LnFeAsO, including coupled structural and antiferromagnetic phase transitions and superconductivity when doped, due to the presence of isoelectronic FeAs layers [10][11][12][13].…”

Structure and properties of EuTSb (T= Cu, Pd, Ag, Pt, Au) and YbIrSb

“…EuPdSb [9] and EuPtSb [8] adopt the TiNiSi type structure with puckered T 3 Sb 3 hexagons (orthorhombically distorted variant of ZrBeSi). In the course of our systematic Mössbauer spectroscopic studies of intermetallic compounds [18][19][20][21][22][23] we were interested in the series of EuTSb animonides since the valence state and magnetic ordering phenomena can be studied through the 121 Sb and 151 Eu nuclei simultaneously. So far, 151 Eu data have only been reported for the 18 K antiferromagnet EuPdSb [16].…”