R
Roger Frech
Researcher at University of Oklahoma
Publications - 189
Citations - 5314
Roger Frech is an academic researcher from University of Oklahoma. The author has contributed to research in topics: Raman spectroscopy & Lithium. The author has an hindex of 38, co-authored 189 publications receiving 4961 citations.
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Journal ArticleDOI
Molecular structures and normal vibrations of trifluoromethane sulfonate (CF3SO3-) and its lithium ion pairs and aggregates
TL;DR: In this article, the Hartree-Fock method was used to study the trifluoromethanesulfonate (triflate) anion, its lithium ion pairs, and several aggregates using the ab initio self-consistent field Hartree Fock method with 3-21+G *, 6-31+G augmented with polarization functions (d type orbitals) on the sulfur atom.
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Raman and FTIR Spectroscopic Study of Li x FePO4 ( 0 ⩽ x ⩽ 1 )
Christopher M. Burba,Roger Frech +1 more
TL;DR: A series of compounds, Li x FePO 4 (0 ≤ x ≤ 1), was prepared by chemical delithiation and investigated with Fourier transform infrared (FTIR) and Raman spectroscopy for the first time.
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Vibrational spectroscopic and electrochemical studies of the low and high temperature phases of LiCo1−x MxO2 (M = Ni or Ti)
Weiwei Huang,Roger Frech +1 more
TL;DR: A spinel structure with the space group Fd3m is unambiguously assigned to LiCoO2 synthesized at 400 °C, according to Raman and infra-red spectra of LT-LiCoO 2 and factor group analysis of the vibrational modes for the layered (R3m) and the spinel (Fd 3m) structure models as mentioned in this paper.
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Infrared Spectroscopic Study of the Phases and Phase Transitions in Poly(ethylene oxide) and Poly(ethylene oxide)-Lithium Trifluoromethanesulfonate Complexes
M.A.K.L. Dissanayake,Roger Frech +1 more
TL;DR: In this paper, the infrared vibrational spectra of high molecular weight poly(ethylene oxide) and complexes with lithium trifluoromethanesulfonate at two different salt concentrations have been measured from 25 to 150 °C.
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Conformational Changes in Diethylene Glycol Dimethyl Ether and Poly(ethylene oxide) Induced by Lithium Ion Complexation
Roger Frech,Weiwei Huang +1 more
TL;DR: In this paper, the authors investigated the conformational changes in diethylene glycol dimethyl ether (diglyme) and high molecular weight poly(ethylene oxide) induced by complexation with LiCF 3 SO 3 ) using Raman scattering and infrared transmission spectroscopy.