Original scientific paper

A Proton Magnetic Resonance and Infrared Study of Colemanite and lnyoite

R. Blinc
S. Maričić ; Department of Structural and Inorganic Chemistry, Institute »Ruder Boskovic«, Zagreb, and Physics Departm ent, Institute »JoZ:ef Stefan«, Ljubljana, Yugoslavia
M. Pintar ; Department of Structural and Inorganic Chemistry, Institute »Ruder Boskovic«, Zagreb, and Physics Departm ent, Institute »JoZ:ef Stefan«, Ljubljana, Yugoslavia

Abstract

A proton magnetic resonance and IR investigation of colemanite,
Ca B30 4 (0H) 3 • H 20 and inyoite, CaBa0a(OH) 5 • 4H20, is in
agreement with the X-ray crystal structure analysist,2 concerning
these two newly proposed formulae. It is confirmed that at room
temperature there is a dynamic distribution of proton sites in the
ferroelectric colem anite, while there is no such effect in inyoite.
Ther~ are two second moment transitions in p. m. r. spectra of
colemanite. The one at about -nooc is due to the onset of
reorientation of water molecules. The second one at T c is discussed
in terms of a dyna mic m odel involving a change from a symmetric
double well potential for the moving protons into an asymmetric
one below Tc·

Keywords

Hrčak ID:

208608

URI

https://hrcak.srce.hr/208608

Publication date:

15.10.1960.

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