Phase transitions of cesium azide at pressures up to 30 GPa studied using in situ Raman spectroscopy

Journal Article · Tue Apr 28 00:00:00 EDT 2015 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4918911· OSTI ID:22402957

Felser, C. ^[1]; Barkalov, O. I. ^[1]; Naumov, P. ^[1]; Palasyuk, T. ^[2]; Evers, J.; Klapötke, T. M. ^[3]

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1. Max-Planck-Institute for Chemical Physics of Solids, Nöthnitzer-Str. 40, 01187 Dresden (Germany)
2. Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw (Poland)
3. Energetic Materials Research, Ludwig-Maximilian University Munich (LMU), Butenandtstrasse 5-13(D), D-81377 Munich (Germany)

Cesium azide has been studied by Raman spectroscopy at pressures up to ≈30 GPa at room temperature. The sequence of phase transitions to Phase III (at 0.5 GPa), Phase IV (at 4.3 GPa), and Phase V (at ≈19 GPa) has been observed in agreement with recent X-ray diffraction studies. Phase III has been found to adopt a monoclinic C2/m structure with two azide anions in nonequivalent positions, where one set of azide anions appears to be orientationally disordered according to the observed Raman spectra. The transition to Phase IV has been associated with orientational ordering of azide anions, while the transition to Phase V has been shown to proceed with a lowering of crystal symmetry. Moreover, spectroscopic features indicate a possible change of bonding in CsN{sub 3} toward formation of covalent bonds at high pressures.

• OSTI ID: 22402957
• Journal Information: Journal of Applied Physics, Vol. 117, Issue 16; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANIONS
AZIDES
CESIUM
CESIUM NITRIDES
CHEMICAL BONDS
CRYSTALS
MONOCLINIC LATTICES
PHASE TRANSFORMATIONS
PRESSURE DEPENDENCE
PRESSURE RANGE GIGA PA
RAMAN SPECTRA
RAMAN SPECTROSCOPY
SYMMETRY
TEMPERATURE RANGE 0273-0400 K
X-RAY DIFFRACTION