Charge transfer in organic electron conductors with coordination complexes determined by infrared absorption spectroscopy

Robles‐Martínez, J. G.; Salmerón‐Valverde, A.; Alonso, E.; Soriano, Conxa; Zehe, A.

doi:10.1016/s0020-1693(00)85869-7

Cited by 9 publications

(3 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Spectroscopic Properties. It is well-known that the degree of charge transfer in the ground state of molecules containing CN groups can be determined from the infrared absorption frequency of the CN stretch mode, when the withdrawing effect of the nitrile group is involved in a molecular system containing a donor counterpart. − However, very similar frequencies were observed in the case of H 2 L (2210 cm -1 ), NiL (2212 cm -1 ), CuL (2211 cm -1 ), and ZnL (2210 cm -1 ). This suggests that the metals modify very slightly the charge distribution of the π-electronic structure versus that of the free ligand.…”

Section: Resultsmentioning

confidence: 93%

Synthesis and Second-Order Nonlinear Optical Properties of New Copper(II), Nickel(II), and Zinc(II) Schiff-Base Complexes. Toward a Role of Inorganic Chromophores for Second Harmonic Generation

Lacroix

Bella

Ledoux³

1996

Chem. Mater.

167

107

View full text Add to dashboard Cite

A new Schiff-base ligand based on the condensation of diaminomaleonitrile and 4-(diethylamino)salicylaldehyde is reported with its copper, nickel, and zinc complexes. Their second-order nonlinear optical properties are investigated by electric field induced second harmonic (EFISH) and ZINDO quantum-chemical calculations to probe the role of the metal center in the nonlinearity. All the complexes exhibit a second-order nonlinear response that is larger than that of the ligand with an hyperpolarizability (β) value of 400 (±100) 10-30 cm5 esu-1 for the zinc derivative at 1.34 μm. Theoretical calculations indicate that the two-level model is inadequate to describe the nonlinearity in such systems.

show abstract

Section: Resultsmentioning

confidence: 93%

Synthesis and Second-Order Nonlinear Optical Properties of New Copper(II), Nickel(II), and Zinc(II) Schiff-Base Complexes. Toward a Role of Inorganic Chromophores for Second Harmonic Generation

Lacroix

Bella

Ledoux³

1996

Chem. Mater.

167

107

View full text Add to dashboard Cite

show abstract

“…A band at 2213 cm -1 is due to a C⋮N stretching mode of the C 18 TCNQ component in the CT complex. The C⋮N stretching band appears at 2228 cm -1 in an infrared spectrum of neutral TCNQ and it shows a low-frequency shift by 5−45 cm -1 in the spectra of the CT complexes consisting of TCNQ. , Therefore, this band can be used as a marker for the formation of the CT complex. In an infrared spectrum of neutral C 18 TCNQ, the C⋮N stretching band appears at 2222 cm -1 .…”

Section: Resultsmentioning

confidence: 99%

“…Degree of Charge Transfer. It is well-known that the frequency of the C⋮N stretching band is related to the degree of charge transfer (ρ), and the value of ρ for the CT complexes consisting of C 18 TCNQ can be derived from the degree of the shift of the C⋮N stretching band. ,,, As references, the peak at 2222 cm -1 of neutral C 18 TCNQ and that at 2184 cm -1 of C 18 TCNQ -1 can be employed. , The C⋮N stretching band of N-TMB·C 18 TCNQ in the CT LB film appears at 2213 cm -1 in Figure , indicating that the value of ρ is about 0.24.…”

Section: Resultsmentioning

confidence: 99%

Preparation and Structural Characterization of Mixed-Stack Charge-Transfer Langmuir−Blodgett Films of 2-Octadecyl-7,7,8,8-tetracyanoquinodimethane and N,N,N‘,N‘-Tetramethylbenzidine

and

Ozaki

2000

Langmuir

View full text Add to dashboard Cite

One-, three-, and seven-layer Langmuir-Blodgett (LB) films of a mixed-stack charge-transfer (CT) complex of 2-octadecyl-7,7,8,8-tetracyanoquinodimethane (C18TCNQ) and N,N,N′,N′-tetramethylbenzidine (N-TMB) were successfully deposited onto CaF2 plates and gold-evaporated glass slides at the surface pressure of 10 mN m -1 . This is the first time that the mixed-stack CT films of N-TMB‚C18TCNQ have been prepared by the LB technique. Ultraviolet-visible-near-infrared (UV-vis-NIR) and infrared spectroscopies have been employed to investigate the formation, degree of charge transfer, molecular orientation, and structure of the CT complex in the LB films. The appearance of a broad absorption band with its center at about 1750 nm reveals that the CT complex in the LB films is in the mixed-stack form. The frequency of a CtN stretching band of C18TCNQ in the CT complex indicates that the degree of charge transfer (F) is about 0.24. A comparison of the infrared band intensities between the transmission and RA spectra suggests that the chromophore planes for both C18TCNQ and N-TMB are nearly parallel to the substrate surface in the CT LB films. This result is in a good agreement with the requirement for the formation of the mixed-stack complex in which the donor and acceptor components should be in a face-to-face contact with each other. The hydrocarbon chain of C18TCNQ is considerably tilted with respect to the substrate normal in the CT LB films. The CT film (LB-doping film) of N-TMB‚C18TCNQ was also prepared by LBand donor-doping techniques. It was found that N-TMB‚C18TCNQ molecules are partly dissolved in the petroleum ether solution during the doping procedure.

show abstract

A new polynitrile π acceptor for electronic switching devices

Wang

Xue

Ouyang

et al. 1995

Chemical Physics Letters

View full text Add to dashboard Cite

Charge transfer in organic electron conductors with coordination complexes determined by infrared absorption spectroscopy

Cited by 9 publications

References 4 publications

Synthesis and Second-Order Nonlinear Optical Properties of New Copper(II), Nickel(II), and Zinc(II) Schiff-Base Complexes. Toward a Role of Inorganic Chromophores for Second Harmonic Generation

Synthesis and Second-Order Nonlinear Optical Properties of New Copper(II), Nickel(II), and Zinc(II) Schiff-Base Complexes. Toward a Role of Inorganic Chromophores for Second Harmonic Generation

Preparation and Structural Characterization of Mixed-Stack Charge-Transfer Langmuir−Blodgett Films of 2-Octadecyl-7,7,8,8-tetracyanoquinodimethane and N,N,N‘,N‘-Tetramethylbenzidine

A new polynitrile π acceptor for electronic switching devices

Contact Info

Product

Resources

About