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81.
Electron paramagnetic resonance (EPR) study of VO2+ doped zinc potassium phosphate hexahydrate single crystal is carried out. The angular variation of the spectra is studied in the three crystallographic planes. The principal value of spin Hamiltonian parameters g and A and the direction cosines which principal axes make with the crystallographic axes are determined. The observed values are site I: g∥=1.9664±0.0002, g⊥=1.9973±0.0002, A∥=150±2×10−4, A⊥=60±2×10−4 cm−1; site II: g∥=1.9276±0.0002, g⊥=1.9921±0.0002, A∥=155±2×10−4 and A⊥=62±2×10−4 cm−1. By comparison of direction cosines of g from EPR with the direction cosines of different bonds obtained from crystal structure data it is ascertained that the VO2+ ion occupies Zn2+ substitutional sites. The optical absorption study of the crystal at room temperature is also carried out. The bands observed in the optical absorption spectrum are attributed to d-d transitions. The EPR results together with the optical data are employed to estimate the molecular orbital (MO) coefficients. These MO coefficients (also called bonding coefficients) are further used to discuss the nature of bonding of VO2+ ion with different ligands in the crystal. 相似文献
82.
Mahmood Khalid Jasim Sunil Kumar Maurya Ksh. Newton Singh Riju Nag 《Entropy (Basel, Switzerland)》2021,23(8)
In this paper, we investigated a new anisotropic solution for the strange star model in the context of Einstein-Gauss-Bonnet (EGB) gravity. For this purpose, we used a linear equation of state (EOS), in particular , (where and are constants) together with a well-behaved ansatz for gravitational potential, corresponding to a radial component of spacetime. In this way, we found the other gravitational potential as well as main thermodynamical variables, such as pressures (both radial and tangential) with energy density. The constant parameters of the anisotropic solution were obtained by matching a well-known Boulware-Deser solution at the boundary. The physical viability of the strange star model was also tested in order to describe the realistic models. Moreover, we studied the hydrostatic equilibrium of the stellar system by using a modified TOV equation and the dynamical stability through the critical value of the radial adiabatic index. The mass-radius relationship was also established for determining the compactness and surface redshift of the model, which increases with the Gauss-Bonnet coupling constant but does not cross the Buchdahal limit. 相似文献
83.
Hall Mobility of As‐Grown Cu2O Thin Films Obtained Via Electrodeposition on Patterned Au Substrates
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Garima Aggarwal Chandan Das Sumanshu Agarwal Sandeep K. Maurya Pradeep R. Nair K.R. Balasubramaniam 《固体物理学:研究快报》2018,12(1)
Hall measurement of an electrodeposited Cu2O film is rendered difficult as the bilayer structure of semiconductor on top of a conductive substrate obviates the measurement. Here, we propose the use of a patterned Au on glass substrate in line/space configuration for the Hall measurement of electrodeposited Cu2O. A continuous, (111) oriented Cu2O film was electrodeposited on 8 μm/2 μm Au‐line/space on glass substrate and Hall measurement was performed. The room temperature Hall measurement of the Cu2O film on the patterned substrate indicates p‐type conduction with a hole concentration of 2.2 × 1017 cm?3 and mobility of 4.7 × 10?3 cm2 V?1 s?1. Additionally, the temperature dependent resistivity exhibits a negative slope that is characteristic of a semiconductor. Therefore, the measured electrical characteristics can be attributed to the electrodeposited Cu2O semiconductor film rather than the conductive substrate. This method can be applied for the Hall measurement of any other electrodeposited semiconductor by optimizing the line/space geometry of the conductive substrate. 相似文献
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Maurya Rajiv K. Sharma Priyamedha Rawat Rajeev Singh Ravi S. R. Bindu 《The European Physical Journal B - Condensed Matter and Complex Systems》2019,92(8):1-5
The European Physical Journal B - It has experimentally been found by Lampo et al. [Biophys. J. 112, 532 (2017)] that, for two different types of cell, the distribution of the diffusivities of... 相似文献
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High-performance liquid chromatographic methods were developed for separation of the enantiomers of mirtazapine and its four process-related substances. The direct separations were achieved on chiral stationary phases containing amylose tris(3,5-dimethylphenylcarbamate) (Chiralpak AD-H), cellulose tris(3,5-dimethylphenylcarbamate) (Chiralcel OD-H) and cellulose tris(4-methylbenzoate) (Chiralcel OJ-H ). The experimental data were utilized to discuss the effects of the mobile phase composition, the nature of the alcoholic modifier and the specific structural features of the analytes on retention and separation. The elution sequence was determined under the optimized separation conditions. 相似文献