Peng Ming-sheng, Li Di-en
Institute of Gemstone and Mineral Materials, Zhongshan University, Guangzhou, 510275 China.
Guang Pu Xue Yu Guang Pu Fen Xi. 2002 Oct;22(5):873-6.
The structural role of Na in Na2-O-SiO2 and Na2O-SiO2-P2O5 glasses was studied using Na K-edge XANES (X-ray near edge structure) spectra. The Na K-edge XANES shows little change with increase in the content of Na2O in Na2O-SiO2 glasses. However, the addition of P into the Na2O-SiO2 system causes dramatic change of the Na K-edge XANES, and the Na K-edge spectra of Na2O-SiO2-P2O5 glasses also change with the increase of P2O5 content. The structural role of Mg in CaMgSi2O6 (Di)--NaAlSi3O8 (Ab) glasses was studied using Mg K-edge XANES spectra. The Mg-O bond distance in these glasses is estimated to be 2.00 +/- 0.04 A. Thus, Mg in these glasses may be five coordinated with oxygen, or Mg may have multiple structural sites, MgIV, MgV and MgVI. The Di-Ab glasses may possess a medium-range ordering structure.
利用钠K边X射线近边结构（XANES）光谱研究了Na在Na₂O - SiO₂和Na₂O - SiO₂ - P₂O₅玻璃中的结构作用。在Na₂O - SiO₂玻璃中，随着Na₂O含量增加，钠K边XANES变化不大。然而，向Na₂O - SiO₂体系中添加P会导致钠K边XANES发生显著变化，并且Na₂O - SiO₂ - P₂O₅玻璃的钠K边光谱也会随着P₂O₅含量的增加而改变。利用镁K边XANES光谱研究了Mg在CaMgSi₂O₆（透辉石） - NaAlSi₃O₈（钠长石）玻璃中的结构作用。这些玻璃中Mg - O键距估计为2.00±0.04埃。因此，这些玻璃中的Mg可能与氧形成五配位，或者Mg可能具有多个结构位点，即MgIV、MgV和MgVI。透辉石 - 钠长石玻璃可能具有中程有序结构。
