Development of highly accurate approximate scheme for computing the charge transfer integral

An X-ray diffraction technique is described that allows determination of crystal structure and the variation of lattice parameters of single crystals as a function of hydrostatic pressure up to 14 kbar and of temperature from 300 K to 12 K. As an example of the technique results are presented on the molecular charge transfer salt α'-(BEDT TTF )2 AuBr 2 (BEDT-TTF = bis(ethylenedithio)-tetrathiafulvalene) to elucidate the nature of a structural phase transition which occurs at 250 K at ambient pressure and 7 kbar at 300 K. The transition, of second order, is characterized by the appearance of ½b* superlattice reflections at high pressure or low temperature but without any drastic change in the basic crystal structure. The isobaric thermal expansions and the isothermal compressibilities are anisotropic, being larger along a than along b and c , though of different magnitudes and directional properties, i. e. the effect of applying pressure at ambient temperature is not equivalent to lowering the temperature at ambient pressure. Transfer integral calculations show that marked dimerization along the stacking axis, already present at 300 K, is related to electronic localization.

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ChemInform Abstract: CHARGE-TRANSFER-INTEGRAL IN PARAMAGNETISCHEN PI-MOLEKUEL-KRISTALLEN

Chemischer Informationsdienst Organische Chemie ◽

10.1002/chin.197140153 ◽

1971 ◽

Vol 2 (40) ◽

Author(s):

ZOLTAN G. SOOS ◽

PAUL J. STREBEL

Keyword(s):

Charge Transfer ◽

Transfer Integral

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The role of charge-transfer integral in determining and engineering the carrier mobilities of 9,10-di(2-naphthyl)anthracene compounds

Chemical Physics Letters ◽

10.1016/j.cplett.2006.02.079 ◽

2006 ◽

Vol 422 (4-6) ◽

pp. 354-357 ◽

Cited By ~ 38

Author(s):

S.C. Tse ◽

S.K. So ◽

M.Y. Yeung ◽

C.F. Lo ◽

S.W. Wen ◽

...

Keyword(s):

Charge Transfer ◽

Transfer Integral

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Polymorph-induced photosensitivity change in titanylphthalocyanine revealed by the charge transfer integral

Nanophotonics ◽

10.1515/nanoph-2018-0223 ◽

2019 ◽

Vol 8 (5) ◽

pp. 787-797 ◽

Cited By ~ 3

Author(s):

Xiaolong Li ◽

Yin Xiao ◽

Shirong Wang ◽

Yuhao Yang ◽

Yongning Ma ◽

...

Keyword(s):

Charge Transfer ◽

Phase Transfer ◽

Average Diameter ◽

Crystal Form ◽

Hole Transfer ◽

Crystal Forms ◽

Type Semiconductor ◽

Reorganization Energies ◽

Transfer Integral ◽

The Relationship

AbstractThe crystal form of semiconductor materials is keenly correlated with the photosensitivity of optoelectronic devices. Thus, understanding the crystal form-dependent photosensitivity mechanism is critical. In this work, the microemulsion phase transfer method was adopted to prepare α- and β-titanylphthalocyanine (TiOPc NPs) with an average diameter of 35 nm. The photosensitivity (E1/2) of α-TiOPc NPs was 2.73 times better than that of β-TiOPc NPs, which was characterized by photoconductors under the same measurement conditions. DFT was performed to explain the relationship between crystal form and photosensitivity by systematically calculating the charge transfer integrals for all possible dimers in the two different crystal forms. The hole and electron reorganization energies of TiOPc were respectively calculated to be 53.5 and 271.5 meV, revealing TiOPc to be a typical p-type semiconductor. The calculated total hole transfer mobility (μ+) ratio (2.83) of α- to β-TiOPc was almost identical to the experimental E1/2 ratio (2.73) and the calculated photogeneration quantum efficiency (ηe-h) ratio (2.23). In addition, the optimum hole transfer routes in the crystal of α- and β-TiOPc were all along with the [1 0 0] crystal orientation, which was determined by the calculated μ+. A high charge transfer mobility leads to a high photosensitive TiOPc crystal. Consequently, these results indicate that the selected theoretical calculation method is reasonable for indirectly explaining the relationship between crystal form and photosensitivity. The TiOPc molecular solid-state arrangements, namely, the crystal forms of TiOPc, have a strong influence on the charge transport behavior, which in turn, affects its photosensitivity.

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Study of charge transfer in FeTi

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075270 ◽

1983 ◽

Vol 41 ◽

pp. 296-297

Author(s):

J. Taft∅

Keyword(s):

Charge Transfer ◽

Charge Distribution ◽

Electron Scattering ◽

Periodic System ◽

Electron Distribution ◽

Scattering Amplitude ◽

Transition Elements ◽

Hartree Fock ◽

Cscl Structure ◽

The Right

It is well known that for reflections corresponding to large interplanar spacings (i.e., sin θ/λ small), the electron scattering amplitude, f, is sensitive to the ionicity and to the charge distribution around the atoms. We have used this in order to obtain information about the charge distribution in FeTi, which is a candidate for storage of hydrogen. Our goal is to study the changes in electron distribution in the presence of hydrogen, and also the ionicity of hydrogen in metals, but so far our study has been limited to pure FeTi. FeTi has the CsCl structure and thus Fe and Ti scatter with a phase difference of π into the 100-ref lections. Because Fe (Z = 26) is higher in the periodic system than Ti (Z = 22), an immediate “guess” would be that Fe has a larger scattering amplitude than Ti. However, relativistic Hartree-Fock calculations show that the opposite is the case for the 100-reflection. An explanation for this may be sought in the stronger localization of the d-electrons of the first row transition elements when moving to the right in the periodic table. The tabulated difference between fTi (100) and ffe (100) is small, however, and based on the values of the scattering amplitude for isolated atoms, the kinematical intensity of the 100-reflection is only 5.10-4 of the intensity of the 200-reflection.

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