The Experts below are selected from a list of 279 Experts worldwide ranked by ideXlab platform

Akihisa Inoue - One of the best experts on this subject based on the ideXlab platform.

W J Botta - One of the best experts on this subject based on the ideXlab platform.

Syed Nisar Ahmed - One of the best experts on this subject based on the ideXlab platform.

  • correlation between optical Electronegativity and refractive index of ternary chalcopyrites semiconductors insulators oxides and alkali halides
    Optical Materials, 2008
    Co-Authors: R R Reddy, Rama K Gopal, K Narasimhulu, Siva Sankara L Reddy, Raghavedra K Kumar, C Krishna V Reddy, Syed Nisar Ahmed
    Abstract:

    Abstract Interesting relationships have been found between energy gap, optical Electronegativity and refractive index for different materials viz. elemental compounds, binary and ternary chalcopyrites, semiconductors, insulators, oxides and alkali halides. An excellent agreement has been obtained from modified Herve and Vandamme relation and the literature values. It can be observed that as the optical Electronegativity (Δχ∗) values for the group of semiconductors with the common cation decreases, their refractive index increases. Compounds with covalent nature like AlSb and ZnS have small magnitude of optical Electronegativity (Δχ∗) and relatively high refractive index. The trend is quite reverse in the case of ionic molecules. This work highlights the significance of the interrelation between energy gap, optical Electronegativity and refractive index.

Yuansheng Jin - One of the best experts on this subject based on the ideXlab platform.

  • Relation of certain quantum chemical parameters to lubrication behavior of solid oxides
    International Journal of Molecular Sciences, 2005
    Co-Authors: Ali Erdemir, Shenghua Li, Yuansheng Jin
    Abstract:

    It is well-documented that certain oxides (such as Re2O7, B2O3, MoO3,\nV2O5, etc.) can provide friction coefficients of 0.1-0.3 to sliding\nsurfaces at elevated temperatures and thus they are often referred to\nas lubricious oxides in the tribology literature. In a recently\nproposed crystal chemical model, Erdemir was able to establish a close\ncorrelation between the reported friction coefficients of such oxides\nand their ionic potentials {[}1]. In the present paper, we expand on\nthis original concept and explore the relevance of two other quantum\nchemical parameters, Electronegativity and chemical hardness, to the\nlubricity of solid oxides. These parameters have already been used by\nscientists to explain the nature of tribochemical interactions between\nvarious oil additives and sliding surfaces. It is conceivable that\nElectronegativity and chemical hardness may also be strongly related to\nthe extent of adhesive interactions and shear rheology of solid oxides\nand hence to their lubricity. The new results have confirmed that\nElectronegativity, like ionic potential, is indeed a valid quantum\nchemistry parameter that can be used in predicting the lubrication\nbehavior of solid oxides. Generally, the higher the Electronegativity\nof the solid oxides is, the lower the friction coefficients will be.\nHowever, chemical hardness did not yield a similar trend. In light of\nthese new findings, we propose some guidelines for the formulation of\nnovel oxide or alloy systems that can lead to the formation of\nlubricious oxides at elevated temperatures. The findings of this study\nmay pave the way for designer-based tribosystems in general and smart\ntribochemical systems in particular in future tribological applications\nsuch as dry machining.

Jianxin Tang - One of the best experts on this subject based on the ideXlab platform.

  • Electronegativity model for barrier formation at metal organic interfaces
    Applied Physics Letters, 2005
    Co-Authors: Jianxin Tang
    Abstract:

    An Electronegativity model is proposed to characterize the variation of charge injection barrier heights at metal/organic interfaces. In contrast to the traditionally used metal work function, barrier heights at interfaces are shown to be linearly dependent on metal Electronegativity for a wide range of organic materials. The physical basis for the better suitability of Electronegativity than work function to describe barrier heights is discussed. While barrier formation is caused by charge transfer between metals and organic semiconductors, the variation of the barrier height is related to the Electronegativity difference of metals. The applicability of the Electronegativity model to compound or alloy electrodes, such as indium tin oxide having no defined Electronegativity, is also exemplified.

  • Electronegativity model for barrier formation at metal/organic interfaces
    Applied Physics Letters, 2005
    Co-Authors: Jianxin Tang
    Abstract:

    An Electronegativity model is proposed to characterize the variation of charge injection barrier heights at metal/organic interfaces. In contrast to the traditionally used metal work function, barrier heights at interfaces are shown to be linearly dependent on metal Electronegativity for a wide range of organic materials. The physical basis for the better suitability of Electronegativity than work function to describe barrier heights is discussed. While barrier formation is caused by charge transfer between metals and organic semiconductors, the variation of the barrier height is related to the Electronegativity difference of metals. The applicability of the Electronegativity model to compound or alloy electrodes, such as indium tin oxide having no defined Electronegativity, is also exemplified.