Abstract

Infrared spectroscopy has been used to study a series of synthetic agardite minerals. Four OH stretching bands are observed at around 3568, 3482, 3362, and 3296 cm^-1. The first band is assigned to zeolitic, non-hydrogen-bonded water. The band at 3296 cm^-1 is assigned to strongly hydrogen-bonded water with an H bond distance of 2.72 Å. The water in agardites is better described as structured water and not as zeolitic water. Two bands at around 999 and 975 cm^-1 are assigned to OH deformation modes. Two sets of AsO symmetric stretching vibrations were found and assigned to the vibrational modes of AsO₄ and HAsO₄ units. Linear relationships between positions of infrared bands associated with bonding to the OH units and the electronegativity of the rare earth elements were derived, with correlation coefficients >0.92. These linear functions were then used to calculate the electronegativity of Eu, for which a value of 1.1808 on the Pauling scale was found.

Univariate and multivariate analyses of rare earth elements by laser-induced breakdown spectroscopy

Chet R. Bhatt, Fang Y. Yueh, and Jagdish P. Singh
Appl. Opt. 56(8) 2280-2287 (2017)

Laser isotope separation of rare earth elements

N. V. Karlov, B. B. Krynetskii, V. A. Mishin, and A. M. Prokhorov
Appl. Opt. 17(6) 856-862 (1978)

Rare Earth Infrared Quantum Counter

L. Esterowitz, A. Schnitzler, J. Noonan, and J. Bahler
Appl. Opt. 7(10) 2053-2070 (1968)

The Quantitative Spectrographic Analysis of the Rare Earth Elements*I. Determination of Samarium in NeodymiumII. Determination of Europium in Samarium

Velmer A. Fassel and Harley A. Wilhelm
J. Opt. Soc. Am. 38(6) 518-526 (1948)

Emission Spectra of the Rare Earth Elements*

William F. Meggers
J. Opt. Soc. Am. 31(2) 157-159 (1941)