论文部分内容阅读
通过Materials Studio软件在建立完整的12CaO·7Al2O3晶体结构模型的基础上逐渐减少Ca原子数,使其形成Ca空位,对钙空位量为0~1.00的12CaO·7Al2O3晶体结构进行几何优化模拟,计算其晶格参量、晶体自由能、化学键布居数及键长等。结果表明:Ca空位对12CaO·7Al2O3晶体结构的稳定性有显著影响,随着Ca空位量的增加,12CaO·7Al2O3晶体晶格参量和晶胞体积逐渐降低,自由能逐渐增加,O—Ca键稳定性变差;当Ca空位量增加到0.75和1.00时,O—Ca键种类由4种减少到3种,且键长增大,从而导致12CaO·7Al2O3晶体的稳定性逐渐降低;分别合成钙空位量为0、0.50和1.00的12CaO·7Al2O3晶体,其在碳酸钠溶液中的分解率随着钙空位量的增加而增加,晶体稳定性与晶体学模拟结果相吻合。
Based on the crystal structure model of 12CaO · 7Al2O3, the number of Ca atoms is gradually reduced by Materials Studio software to form Ca vacancies. The crystal structure of 12CaO · 7Al2O3 crystal with 0 ~ 1.00 vacancy is simulated geometrically. Lattice parameters, crystal free energy, the number of chemical bonds and bond length and so on. The results show that Ca vacancy has a significant influence on the crystal structure of 12CaO · 7Al2O3. With the increase of Ca vacancies, the crystal lattice parameters and unit cell volume of 12CaO · 7Al2O3 crystal decrease gradually, the free energy increases gradually and the O-Ca bond stabilizes When Ca vacancy amount is increased to 0.75 and 1.00, the type of O-Ca bond is reduced from 4 to 3, and the bond length increases, which leads to the gradual decrease of the stability of 12CaO · 7Al2O3 crystal. Calcium vacancies The amounts of 12CaO · 7Al2O3 crystals in the amounts of 0, 0.50 and 1.00 increased with the increase of calcium vacancies in the sodium carbonate solution, and the crystal stability was consistent with the results of the crystallographic simulation.