| From telescope lenses to fiber optics to smartphone screens,glass has played a key driving role in human history.Unlike crystalline materials,glass can have almost any composition and stoichiometry,creating unlimited opportunities for the development of new glass with unusual properties.However,such a large composition space also makes the traditional experimental trial and error method inefficient.To solve this problem,researchers have developed models for calculation of glass properties to accelerate the design and optimization of new glass materials.However,due to the lack of understanding of glass structure,the current models for calculation of glass properties have some problems,such as low accuracy,poor interpretability and poor expansion ability,which greatly limit the composition design of new glass in practical applications.Therefore,based on the analysis and exploration of glass structure theory,this paper explores the structure of glass by designing an ideal atomic structure model,reveals the nature of glass,and proposes that glass can be described as a glassy compound with same composition,or approximately described as a statistical ensemble of its nearest glassy compounds.The glass composition-structure-property（GCSP）model is established by quantitative description of mathematical formula.The structure and physical properties of the glass,as well as the local structure and luminescence properties of the rare earth doped glass are calculated accurately by the GCSP model.Finally,base on the inverse derivation of GCSP model,the design of glass compositions with specific properties is realized:（1）Based on the analysis and exploration of the glass structure theory,the structure characteristics of Si O2 glass are reproduced by designing an ideal atomic structure model.It is considered that glass is the glass state of the compound with same composition,and the structure of glass is approximately composed of quasi-ordered structural units of the compound of a certain size,and the properties of glass are equal to the properties of the glass state of the compound.Further,if the studied glass composition cannot form a compound,the glass can be approximated as a statistical ensemble of its nearest neighbor glassy compounds.and the structure of the glass can be approximated as consisting of quasi-ordered structural units of the nearest neighbor compounds of a certain size,and the glass property is approximately equal to the weighted glass properties of the nearest neighbor glassy compounds.Through mathematical derivation,the above conclusion is described quantitatively,and finally the glass composition-structure-property（GCSP）model is established.（2）The GCSP model is applied to the calculation and study of the structure and physical properties of silicate glass,borosilicate glass and chalcogenide glass.In the calculation of the structure and physical properties of silicate glasses,the radial distribution function g（r）and structure factor S（q）of Si O2-Al2O3-Ca O-Na2O glasses are calculated by using the GCSP model,and the calculated results are in good agreement with the MD simulation results.The density,Young’s modulus,glass transition temperature,thermal expansion coefficient,refractive index and dispersion of Si O2-Al2O3-Ca O-Na2O glasses were calculated by GCSP model.The maximum relative errors between calculated values and experimental values were 1.02%,7.06%,1.59%,4.69%,0.27%and 0.37%,respectively.In the calculation of structure and physical properties of borosilicate glasses,the fractions of structural group[BO4]of Na2O-B2O3-Si O2 glasses are calculated by using GCSP model.The maximum relative error between the calculated values and the experimental values is 6.01%.The density and Young’s modulus of Na2O-B2O3-Si O2 glasses are calculated by using GCSP model.The maximum relative errors between the calculated and experimental values are 2.60%and 9.68%,respectively.In the calculation of the structure and physical properties of the chalcogenide glasses,the average coordination numbers of the Ge-As-Se glasses was calculated by using GCSP model.The maximum relative error between the calculated values and the experimental values was 0.94%.The Young modulus,glass transition temperature,refractive index and nonlinear refractive index of the Ge-As-Se glass were calculated by using the GCSP model.The maximum relative errors between the calculated and experimental values are 7.98%,9.68%,0.59%and 7.89%,respectively.The above results prove that the GCSP model can accurately calculate the structural characteristics and physical properties of glasses.Finally,through quantitative calculation of GCSP model,the microscopic mechanism of boron anomaly in Na2O-B2O3-Si O2glass is revealed,and the composition region（Na2O:6～10 mol%,Ca O:0～5 mol%,Al2O3:16～23 mol%）of Si O2-Al2O3-Ca O-Na2O glasses with low density and high Young’s modulus and the glass composition region（Ge:0～5 mol%,As:28～37 mol%）of Ge-As-Se glasses with high nonlinear refractive index are found.（3）The GCSP model has been applied to calculate the local structure and luminescence properties of Nd3+doped phosphate glasses and Yb3+doped tellurate glasses.In the calculation of the local structure and luminescence properties of Nd3+doped phosphate glasses,the gRe（r）,Nd3+coordination number and SRe（q）of Nd3+doped Li2O-Mg O-Al2O3-P2O5 glasses were calculated using the GCSP model.The calculated results are basically consistent with the molecular dynamics simulation results.The GCSP model is used to calculate the stimulated emission cross section and fluorescence lifetime of Nd3+doped Li2O-Mg O-Al2O3-P2O5 glasses.The maximum relative errors between the calculated values and the experimental values are9.03%and 8.45%,respectively.In the calculation of the luminescence properties of Yb3+tellurite glasses,the excited cross section and fluorescence lifetime of Yb3+doped Ba O-Nb2O5-Ge O2-Te O2 glass are calculated by using GCSP model.The maximum relative errors between the calculated values and the experimental values are 9.03%and 8.45%,respectively.These results indicate that the GCSP model can be used to quantitatively calculate the local structural characteristics and luminescence properties of rare earth doped glass.Finally,through the quantitative calculation of GCSP model,the composition region（Li2O:1～7 mol%,Mg O:10～18mol%,Al2O3:0～7 mol%）of Nd3+doped Li2O-Mg O-Al2O3-P2O5 glasses with high excited cross section and long fluorescence life and the composition region（Ba O:5～12 mol%,Nb2O5:0～5mol%,Ge O2:10～15 mol%）of Yb3+doped Ba O-Nb2O5-Ge O2-Te O2 glasses with high excited cross section and long fluorescence lifetime are found.（4）The GCSP model was reversely derived,and a design system for glass composition with specific properties was constructed.Through the system,9 glass compositions with refractive index and dispersion values of 1.50 and 8×10-3,10 glass compositions with glass transition temperature and thermal expansion coefficient values of 500°C and 1.00×10-5/K,8glass compositions with density and Young’s modulus values of 2.50 g/cm3 and 75 Gpa,and 6glass compositions with nonlinear refraction values of 8.00×10-14 cm2/W were designed.It is noting that the experimental glass compositions similar to the designed glass compositions were found in the literature,whose properties are in good agreement with the target properties.It is indicated that the design system of glass composition with proscribed properties can be applied to the design of glass composition with targeted properties. |
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