ChemInform Abstract: Magnetic, Optical, and Electronic Properties of the Phosphide Oxides LnZnPO (Ln: Y, La—Nd, Sm, Gd, Dy, Ho).

Abstract

Ln: Y, La-Nd, Sm, Gd, Dy, Ho). -Single crystals of the title compounds are prepared by reaction of the rare earth metals, ZnO, and red phosphorus in a NaCl/KCl flux (1170 K, evacuated silica tube, 11-24 d). The structures of LnZnPO with Ln: Y, Sm, Gd, and Dy are determined by single crystal XRD (space group R3m, Z = 6). The structures are composed of alternate stacks of (Ln 3+ O 2-) and (Zn 2+ P 3-) layers with covalent Ln-O and Zn-P bonding within and weak ionic bonding between the layers. Susceptibility measurements on β-CeZnPO, β-PrZnPO, and GdZnPO reveal Curie--Weiss paramagnetism with experimental magnetic moments of 2.31, 3.60, and 7.72 μB/Ln atom, respectively. β-CeZnPO and β-PrZnPO show antiferromagnetic ordering with Neel temperatures of 7.4 K and 2.2 K. GdZnPO exhibits no magnetic ordering down to 2 K. Single crystal NIR/Vis absorption spectra measured for the compounds with Ln: Y, La, Pr, Nd, Sm, Dy reveal unexpected variations for the optical band gap of these phosphide oxides. For Ln: Pr, Nd, Sm, Dy, Ho f-f electronic transitions with well resolved ligand-field splittings are observed in the range 6000-20000 cm -1 . -(LINCKE, H.; GLAUM*, R.; DITTRICH, V.; TEGEL, M.; JOHRENDT, D.; HERMES, W.; MOELLER, M. H.; NILGES, T.; POETTGEN, R.; Z. Anorg. Allg.

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)

“…Similar to the phosphide systems (see the electronic structure calculations of Ce-RuPO [9] and PrZnPO [12]), we can assume strong covalent RE-O and T-Sb bonding within and weak ionic-like bonding between the layers.…”

“…The quaternary phosphide oxides RETPO (RE = rare earth metal; T = transition metal) with T = Mn, Fe, Co, Ni, Zn, Ru, Os [1][2][3][4][5][6][7][8][9][10][11][12] have intensively been studied in the last 15 years with respect to synthesis conditions and crystal chemistry.…”

“…The structures are composed of two different layers [RE 3+ O 2-] and [T 2+ P 3-] with essentially covalent RE-O and T-P bonding within and weak ionic bonding between the layers. Only in the REZnPO series one observes dimorphism with a rhombohedral high-temperature structure [4,5,12]. So far more than 40 RETPO compounds are known.…”

“…LaFePO [6] and LaNiPO [7,11] show a transition to a superconducting state at 3.2 and 4.3 K, respectively. Paramagnetic behavior has been observed for ß-CeZnPO, ß-PrZnPO, GdZnPO [12], CeRuPO and CeOsPO [9]. Among these compounds CeRuPO is a rare example for a ferromagnetic Kondo system.…”

“…In the course of our systematic studies of the magnetic and optical properties of these transparent pnictide oxides [5,12], we have reinvestigated the RETSbO series. Herein we report on single crystal X-ray data of REMnSbO (RE = La, Ce, Sm), LaZnSbO and NdZnSbO, and a detailed 121 Sb Mössbauer spectroscopic study of these two series.…”