Correlation bet ween the elastic and the vibronic behavior of TiO_(2) and their responses to thevariation of crystal size,applied pressure,and measuring temperature has been investig ated basedon the bond order-length...Correlation bet ween the elastic and the vibronic behavior of TiO_(2) and their responses to thevariation of crystal size,applied pressure,and measuring temperature has been investig ated basedon the bond order-length-strength correlation mechanism.Theoretical reproduction of themeasurements clarified that.(i)the elastic modulus(B)and the Raman shifts(△ω)are stronglycorrelated and we can know either one of the B or the △ω from the other;(i)the under-coordination induced cohesive energy loss and the energy density gain in the surface up to skindepth determines the size effect;(ii)bond expansion and bond weakening due to thermalvibration originat es the thermally softened elastic modulus and the Raman shifts;and(iv)bondcompression and bond strengthening results in the mechanically stiffened elastic modulus and theRaman shifts.With the developed premise,one can predict the changing trends of the concernedproperties with derivatives of quantitative information of the atomic cohesive energy,bindingenergy density,Debye tempera ture,and nonlinear compressibility of the specimen.展开更多
基金support from the Special Project for Nanotechnology of Shanghai(No.1052nm02700)the Key laboratory of new ceramics and fine processes at Tsinghua University and MOE(RG15/09)of Singapore is gratefully acknowledged.
文摘Correlation bet ween the elastic and the vibronic behavior of TiO_(2) and their responses to thevariation of crystal size,applied pressure,and measuring temperature has been investig ated basedon the bond order-length-strength correlation mechanism.Theoretical reproduction of themeasurements clarified that.(i)the elastic modulus(B)and the Raman shifts(△ω)are stronglycorrelated and we can know either one of the B or the △ω from the other;(i)the under-coordination induced cohesive energy loss and the energy density gain in the surface up to skindepth determines the size effect;(ii)bond expansion and bond weakening due to thermalvibration originat es the thermally softened elastic modulus and the Raman shifts;and(iv)bondcompression and bond strengthening results in the mechanically stiffened elastic modulus and theRaman shifts.With the developed premise,one can predict the changing trends of the concernedproperties with derivatives of quantitative information of the atomic cohesive energy,bindingenergy density,Debye tempera ture,and nonlinear compressibility of the specimen.
