INFRARED TRANSMISSION SPECTRA OF SINGLE CRYSTALS OF CUBIC PEROVSKITE FLUORIDES.

Loading...
Thumbnail Image

Date

1966

Journal Title

Journal ISSN

Volume Title

Publisher

Ohio State University

Research Projects

Organizational Units

Journal Issue

Abstract

The infrared transmission spectra of thin single crystals of $KNiF_{3}, KMgF_{3}, KMnF_{3}, KZnF_{3}, KCOF_{3}$ and $RbMnF_{3}$ have been investigated from $1500 cm^{-1}$ to $20 cm^{-1}$ at $300^{\circ}K$ and nitrogen temperatures. The spectra showed three broad absorptions corresponding to the three allowed infrared active optic modes in these cubic perovskite crystals. In the regions between these broad absorptions the samples transmitted from 50 per cent to 90 per cent of the incident energy when cooled to nitrogen temperatures. In these regions absorption bands have been observed which sharpen and shift to higher frequencies upon cooling to nitrogen temperatures. A fitting scheme is proposed to account for these absorptions as combinations of phonon modes from the edge of the Brillouin zone.

Description

Author Institution: Spectroscopy Laboratory and Research Laboratory of Electronics Massachusetts Institute of Technology
The work of the Spectroscopy Laboratory is supported in part by the National Science Foundation, Grant No. GP 4923. This work of the Research Laboratory of Electronics is supported in part by the Joint Services Electronics Program under contract DA36-039-AMC-03200(E).

Keywords

Citation