Abstract

Polarized optical absorption spectroscopy is a standard technique used for determining the bond angle of an OH dipole aligned at an angle, θ, to the threefold c-axis of a trigonal crystal. Optical absorption spectra are measured with the electric vector, E, of the incident light both perpendicular and parallel to the trigonal symmetry axis. The dipole bond angle is usually calculated with the use of the following expression: (α⊥<i>c</i>)/(α∥<i>c</i>) = (1.5 sin²θ)/(3 cos²θ) = (1/2) tan²θ where θ is the OH dipole bond angle to the <i>c</i>-axis, and α⊥<i>c</i> and α∥<i>c</i> are the absorption coefficients of the measured IR bands with <b>E</b>⊥<i>c</i> and <b>E</b>∥<i>c</i>, respectively.

Optical Properties of Trigonal Selenium in the Vacuum Ultraviolet*

Algird G. Leiga
J. Opt. Soc. Am. 58(7) 880-884 (1968)

Accurate determination of the indices of refraction of nonlinear optical crystals

John F. H. Nicholls, Brian Henderson, and Bruce H. T. Chai
Appl. Opt. 36(33) 8587-8594 (1997)

Resolving the bond angle of a plasmonic metamolecule

Yanrong Wang, Ruqiang Zheng, Yufeng Ding, Wenjun Fan, Dahe Liu, Jing Zhou, and Jinwei Shi
Optica 4(9) 1092-1097 (2017)

High-precision determination of the cut angle of an electro-optic crystal by conoscopic interference

Qi Lu, Shenghao Wang, You Zhou, Shijie Liu, and Jianda Shao
Appl. Opt. 57(24) 6886-6891 (2018)

Trigonal Crystal-Field Energy Levels of Sm³⁺ in CaF₂ (Type I)

Norman Rabbiner
J. Opt. Soc. Am. 59(5) 588-591 (1969)