Yadav Arti, Khasa Satish, Hooda Ashima, Dahiya Manjeet S, Agarwal Ashish, Chand Prem
Department of Physics, Deenbandhu Chhotu Ram University of Science and Technology, Murthal, Sonipat 131039, India.
Department of Physics, Deenbandhu Chhotu Ram University of Science and Technology, Murthal, Sonipat 131039, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2016 Mar 15;157:129-137. doi: 10.1016/j.saa.2015.12.027. Epub 2015 Dec 22.
Glasses having composition 7NiO∙23Li2O∙20Bi2O3∙50B2O3, 7V2O5∙23Li2O∙20Bi2O3∙50B2O3 and x(2NiO∙V2O5)∙(30-x)Li2O∙50B2O3∙20Bi2O3 (with x=0, 2, 5, 7 & 10 mol%) prepared through melt-quench route are explored by analyzing density, impedance spectroscopy and electron paramagnetic resonance (EPR). It is found that both density and molar volume increase with an increase in substitution of 2NiO∙V2O5 in the base glass matrix. Different dielectric parameters viz. dielectric loss (ε), electrical modulus (M), loss tangent (tanδ) etc. are evaluated and their variations with frequency and temperature are analyzed which reveals that these glasses exhibit a non-Debye relaxation behavior. A phenomenal description of the capacitive behavior is obtained by considering the circuitry as a parallel combination of bulk resistance (Rb) and constant phase element (CPE). The conduction mechanism is found to follow Quantum Mechanical Tunneling (QMT) model. Spin Hamiltonian Parameters (SHPs) and covalency rates are calculated from the EPR spectra of vanadyl ion. The observed EPR spectra confirmed that V(4+) ion exists as vanadyl ion in the octahedral coordination with tetragonal compression.
通过对密度、阻抗谱和电子顺磁共振（EPR）进行分析，研究了采用熔体淬火法制备的成分分别为7NiO∙23Li2O∙20Bi2O3∙50B2O3、7V2O5∙23Li2O∙20Bi2O3∙50B2O3以及x(2NiO∙V2O5)∙(30 - x)Li2O∙50B2O3∙20Bi2O3（x = 0、2、5、7和10摩尔%）的玻璃。研究发现，在基础玻璃基体中，随着2NiO∙V2O5替代量的增加，密度和摩尔体积均增大。评估了不同的介电参数，即介电损耗（ε）、电模量（M）、损耗角正切（tanδ）等，并分析了它们随频率和温度的变化，结果表明这些玻璃呈现非德拜弛豫行为。通过将电路视为体电阻（Rb）和恒相位元件（CPE）的并联组合，获得了电容行为的显著描述。发现导电机制遵循量子力学隧穿（QMT）模型。从钒氧基离子的EPR谱计算了自旋哈密顿参数（SHPs）和共价率。观察到的EPR谱证实，V(4+)离子以八面体配位且具有四方压缩的钒氧基离子形式存在。
