The crystal structure of neodymium and europium chromate heptahydrate: Synthesis, infrared spectra, and thermal behavior of lanthanoid chromate heptahydrates, (Ln sub 2 (CrO sub 4 ) sub 3 (H sub 2 O) sub 5 )ter dot 2H sub 2 O (Ln=La, Pr, Nd, Sm, Eu, Gd)

Journal Article · Wed May 01 00:00:00 EDT 1991 · Journal of Solid State Chemistry; (United States)

DOI:https://doi.org/10.1016/0022-4596(91)90250-L· OSTI ID:7200814

Leppaaaho, J; Valkonen, J ^[1]

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1. Univ. of Jyvaaskylaa (Finland)

The crystal structures of Nd{sub 2}(CrO{sub 4}){sub 3}{center dot}7H{sub 2}O and Eu{sub 2}(CrO{sub 4}){sub 3}{center dot}7H{sub 2}O were determined by the conventional single-crystal X-ray diffraction technique. In addition, unit cell dimensions were measured for La{sub 2} (CrO{sub 4}){sub 3}{center dot}7H{sub 2}O and Sm{sub 2}(CrO{sub 4}){sub 3}{center dot}7H{sub 2}O. All these compounds are isostructural. Crystals are monoclinic, space group P2{sub 1}/c. For Nd{sub 2}(CrO{sub 4}){sub 3}{center dot}7H{sub 2}O, a=8.052(4){angstrom}, b=19.143(4){angstrom}, c=13.326(6){angstrom}, {beta}=128.15(4){degree}, Z=4, D{sub x}=3.14 Mg{center dot}m{sup {minus}3}, T=296(1); and for Eu{sub 2}(CrO{sub 4}){sub 3}{center dot}7H{sub 2}O, a=7.965(3){angstrom}, b=18.985(4){angstrom}, c=13.185(4){angstrom}, {beta}=128.00(2){degree}, Z=4, D{sub x}=3.29 Mg{center dot}m{sup {minus}3}, T=296(1). Ln atoms are nine-coordinated so that the coordination polyhedron is a tricapped trigonal prism for Ln1 and a monocapped square antiprism for Ln2. Structures form a three-dimensional network. Unit cell dimensions for La{sub 2}(CrO{sub 4}){sub 3}{center dot}7H{sub 2}O are a=8.181(6){angstrom}, b=19.294(6){angstrom}, c=13.436(8){angstrom}, {beta}=128.09(6){degree} and those for Sm{sub 2}(CrO{sub 4}){sub 3}{center dot}7H{sub 2}O are a=7.975(9){angstrom}, b=19.00(1){angstrom}, c=13.18(3){angstrom} and {beta}=127.5(2){degree}. Thermal behavior was investigated and IR spectra were recorded for Ln{sub 2}(CrO{sub 4}){sub 3}{center dot}7H{sub 2}O (Ln=La, Pr, Nd, Sm, Eu, Gd).

• OSTI ID: 7200814
• Journal Information: Journal of Solid State Chemistry; (United States), Vol. 92:1; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
36 MATERIALS SCIENCE
CHROMATES
CHEMICAL PREPARATION
INFRARED SPECTRA
THERMAL GRAVIMETRIC ANALYSIS
EUROPIUM COMPOUNDS
GADOLINIUM COMPOUNDS
LANTHANUM COMPOUNDS
NEODYMIUM COMPOUNDS
CRYSTAL STRUCTURE
PRASEODYMIUM COMPOUNDS
SAMARIUM COMPOUNDS
ABSORPTION SPECTROSCOPY
EXPERIMENTAL DATA
HYDRATES
LATTICE PARAMETERS
MONOCLINIC LATTICES
CHEMICAL ANALYSIS
CHROMIUM COMPOUNDS
CRYSTAL LATTICES
DATA
GRAVIMETRIC ANALYSIS
INFORMATION
NUMERICAL DATA
OXYGEN COMPOUNDS
QUANTITATIVE CHEMICAL ANALYSIS
RARE EARTH COMPOUNDS
SPECTRA
SPECTROSCOPY
SYNTHESIS
THERMAL ANALYSIS
TRANSITION ELEMENT COMPOUNDS
400201* - Chemical & Physicochemical Properties
400102 - Chemical & Spectral Procedures
360204 - Ceramics
Cermets
& Refractories- Physical Properties