POLYMORPHISM OF RARE EARTH DISILICIDES

Journal Article · Tue Dec 01 04:00:00 EST 1959 · Journal of Physical Chemistry (U.S.)

DOI:https://doi.org/10.1021/j150582a030· OSTI ID:4201525

Perri, J A; Banks, E; Post, B

The results of x-ray-diffraction studies of the stability ranges of two polymorphic forms of the tetragonal phase in Eu. Pr. Nd. Sm, Cd. Y. and Dy disilicides are given. NdSi/sub /2 appear to be orthorhombic at room temperature. The (101) and (103) reflections of PrSi/sub 2/ broaden as the temperature is lowered to -120 deg C and resolve into two peaks indicating the orthorhonibic form. Peak broadening was observed in the (200) and (020) reflections of EuSi/ sub 2/ at 150 deg C indicating onset of the orthorhombic distortion. No comparable broadening of peaks was detected for LaSi/sub 2/ or CeSi/sub 2/ at - 160 deg C. Lattice dimensions were determined at the indicated temperatures for PrSi/sub 2/ (l30 deg C), SmSi/sub 2/(47O deg C), GdSi/sub 2/(460 deg C), 10ySi/ sub 2/(585 deg C), and YSi/sub 2/(545 deg C). (C.J. G.)

• Research Organization: Polytechnic Inst. of Brooklyn
• Sponsoring Organization: USDOE
• NSA Number: NSA-14-005117
• OSTI ID: 4201525
• Journal Information: Journal of Physical Chemistry (U.S.), Journal Name: Journal of Physical Chemistry (U.S.) Vol. Vol: 63; ISSN JPCHA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ALLOTROPY
CERIUM COMPOUNDS
CHEMISTRY
DIFFRACTION
DYSPROSIUM
EUROPIUM
GADOLINIUM
LANTHANUM COMPOUNDS
LATTICES
NEODYMIUM
PRASEODYMIUM
QUANTITATIVE ANALYSIS
RARE EARTHS
SAMARIUM
SILICIDES
STABILITY
TEMPERATURE
X RADIATION
YTTRIUM