Dimerized Organic Linear-Chain Conductors and the Unambiguous Experimental Determination of Electron-Molecular-Vibration Coupling Constants

Rice, M. J.; Lipari, N. O.; Strässler, S.

doi:10.1103/physrevlett.39.1359

Cited by 189 publications

(63 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The EMV interaction was first studied to interpret the strong infrared signal in the reflectivity polarized along the stacking axis in K-TCNQ [48]. Rice et al, reported a symmetric dimer model and presented a comprehensive explanation for the EMV interaction [49].…”

Section: Electron-molecular Vibration (Emv) Coupling In Bedt-ttfmentioning

confidence: 99%

Infrared and Raman Studies of Charge Ordering in Organic Conductors, BEDT-TTF Salts with Quarter-Filled Bands

Yakushi

2012

Crystals

View full text Add to dashboard Cite

This paper reviews charge ordering in the organic conductors, β″-(BEDT-TTF) (TCNQ), θ-(BEDT-TTF) 2 X, and α-(BEDT-TTF) 2 X. Here, BEDT-TTF and TCNQ represent bis(ethylenedithio)tetrathiafulvalene and 7,7,8,8-tetracyanoquinodimethane, respectively. These compounds, all of which have a quarter-filled band, were evaluated using infrared and Raman spectroscopy in addition to optical conductivity measurements. It was found that β″-(BEDT-TTF)(TCNQ) changes continuously from a uniform metal to a chargeordered metal with increasing temperature. Although charge disproportionation was clearly observed, long-range charge order is not realized. Among six θ-type salts, four compounds with a narrow band show the metal-insulator transition. However, they maintain a large amplitude of charge order (Δρ~0.6) in both metallic and insulating phases. In the X = CsZn(SCN) 4 salt with intermediate bandwidth, the amplitude of charge order is very small (Δρ < 0.07) over the whole temperature range. However, fluctuation of charge order is indicated in the Raman spectrum and optical conductivity. No indication of the fluctuation of charge order is found in the wide band X = I 3 salt. In α-(BEDT-TTF) 2 I 3 the amplitude of charge order changes discontinuously from small amplitude at high temperature to large amplitude (Δρ max~0 .6) at low temperature. The long-range chargeordered state shows ferroelectric polarization with fast optical response. The fluctuation of multiple stripes occurs in the high-temperature metallic phase. Among α-(BEDT-TTF) 2 MHg(SCN) 4 (X = NH 4 , K, Rb, Tl), the fluctuation of charge order is indicated only in the X = NH 4 salt. α′-(BEDT-TTF) 2 IBr 2 shows successive phase transitions to the ferroelectric state keeping a large amplitude of charge order (Δρ max~0 .8) over the whole temperature range. It was found that the amplitude and fluctuation of charge order in these compounds is enhanced as the kinetic energy (bandwidth) decreases. OPEN ACCESSCrystals 2012, 2 1292

show abstract

Section: Electron-molecular Vibration (Emv) Coupling In Bedt-ttfmentioning

confidence: 99%

Infrared and Raman Studies of Charge Ordering in Organic Conductors, BEDT-TTF Salts with Quarter-Filled Bands

Yakushi

2012

Crystals

View full text Add to dashboard Cite

show abstract

“…Lucovsky and White [19] have shown (for the IV-VI narrow gap semiconductors) that this phenomenon leads to a high value of the transverse effective charge. Rice, Lipari and Strässler [20] developed the theory for the infrared spectra for phonons coupled to charge excitations. In Fig.…”

Section: Resonating Bonds Coupled To Phononsmentioning

confidence: 99%

Spin, charge, and bonding in transition metal mono-silicides

Marel

Damascelli

Schulte

et al. 1998

Physica B: Condensed Matter

View full text Add to dashboard Cite

We review some of the relevant physical properties of the transition metal mono-silicides with the FeSi structure (CrSi, MnSi, FeSi, CoSi, NiSi, etc) and explore the relation between their structural characteristics and the electronic properties. We confirm the suggestion orginally made by Pauling, that the FeSi structure supports two quasi-atomic d-states at the transition metal atom. This shell contains from 0 to 4 electrons in the sequence CrSi to NiSi. In FeSi the two quasi-atomic d-electrons are responsible for the high temperature S = 1 state, which is compensated for T=0 by two itinerant electrons associated with the Fe-Si resonance bonds.

show abstract

“…Characteristic features of both the → E and → E spectra are mid-infrared electronic bands and strong molecular vibrational modes below approximately 1500 cm −1 . Most of the vibrational features in the 600-1500 cm −1 frequency range are known to originate from the coupling of the totally symmetrical modes of the BEDT-TTF molecule with low-lying electronic transitions within the broken symmetry dimerized structure [10,11]. The optical conductivity spectra display low-energy electronic excitations at 2800 cm and splitting of the vibrational features.…”

Section: Spectral Investigationsmentioning

confidence: 99%

Vibrational spectra of two BEDT-TTF-based organic conductors: charge order

et al. 2009

View full text Add to dashboard Cite

Abstract:Infrared and Raman investigations of two phases of bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) based organic conductors with the same CF 3 CF 2 SO − 3 anion: β'-(BEDT-TTF) 2 CF 3 CF 2 SO 3 and δ'-(BEDT-TTF) 2 CF 3 CF 2 SO 3 , are shortly reviewed and compared with the most typical infrared properties of the family of (BEDT-TTF) 2 RR'SO 3 organic conductors, where R = SF 5 , CF 3 , and R' are CH 2 , CF 2 , CHF, CHFCF 2 , and CH 2 CF 2 . The role of the molecular structur and spatial organization of the counterions is discussed.

show abstract

Dimerized Organic Linear-Chain Conductors and the Unambiguous Experimental Determination of Electron-Molecular-Vibration Coupling Constants

Cited by 189 publications

References 16 publications

Infrared and Raman Studies of Charge Ordering in Organic Conductors, BEDT-TTF Salts with Quarter-Filled Bands

Infrared and Raman Studies of Charge Ordering in Organic Conductors, BEDT-TTF Salts with Quarter-Filled Bands

Spin, charge, and bonding in transition metal mono-silicides

Vibrational spectra of two BEDT-TTF-based organic conductors: charge order

Contact Info

Product

Resources

About