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Updated: Aug 7, 2026

A Novel Technique for Raman Analysis of Highly Radioactive Samples Using Any Standard Micro-Raman Spectrometer
Published on: April 12, 2017
Electron paramagnetic resonance, optical absorption and IR spectroscopic studies of the sulphate mineral apjohnite
S Lakshmi Reddy1, G Siva Reddy, D L Wain
1Department of Physics, S.V.D. College, Kadapa 516003, India.
Abstract:
Apjohnite, a naturally occurring Mn-bearing pseudo-alum from Terlano, Bolzano, Italy, has been characterized by EPR, optical, IR and Raman spectroscopy. The optical spectrum exhibits a number of electronic bands around 400 nm due to Mn(II) ion in apjohnite. From EPR studies, the parameters derived, g=2.0 and A=8.82 mT, confirm MnO(H(2)O)(5) distorted octahedra. The presence of iron impurity in the mineral is reflected by a broad band centered around 8400 cm(-1) in the NIR spectrum. A complex band profile appears strongly both in IR and Raman spectra with four component bands around 1100 cm(-1) due to the reduction of symmetry for sulphate ion in the mineral. A strong pair of IR bands at 1681 and 1619 cm(-1) with variable intensity is a proof for the presence of water in two states in the structure of apjohnite.
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