(東北大學(xué) 材料與冶金學(xué)院，沈陽(yáng) 110819)
摘 要: 通過(guò)Materials Studio軟件在建立完整的12CaO？7Al2O3晶體結(jié)構(gòu)模型的基礎(chǔ)上逐漸減少Ca原子數(shù)，使其形成Ca空位，對(duì)鈣空位量為0~1.00的12CaO？7Al2O3晶體結(jié)構(gòu)進(jìn)行幾何優(yōu)化模擬，計(jì)算其晶格參量、晶體自由能、化學(xué)鍵布居數(shù)及鍵長(zhǎng)等。結(jié)果表明：Ca空位對(duì)12CaO？7Al2O3晶體結(jié)構(gòu)的穩(wěn)定性有顯著影響，隨著Ca空位量的增加，12CaO？7Al2O3晶體晶格參量和晶胞體積逐漸降低，自由能逐漸增加，O—Ca鍵穩(wěn)定性變差；當(dāng)Ca空位量增加到0.75和1.00時(shí)，O—Ca鍵種類由4種減少到3種，且鍵長(zhǎng)增大，從而導(dǎo)致12CaO？7Al2O3晶體的穩(wěn)定性逐漸降低；分別合成鈣空位量為0、0.50和1.00的12CaO？7Al2O3晶體，其在碳酸鈉溶液中的分解率隨著鈣空位量的增加而增加，晶體穩(wěn)定性與晶體學(xué)模擬結(jié)果相吻合。
關(guān)鍵字: 12CaO？7Al2O3；晶體結(jié)構(gòu)；穩(wěn)定性；鈣空位；計(jì)算機(jī)模擬
（School of Materials and Metallurgy, Northeastern University, Shenyang 110819, China）
Abstract:The geometry optimization simulation of 12CaO？7Al2O3 crystal with different calcium atom vacancies from 0 to 1 was performed by gradually decreasing calcium atoms based on the establishment of complete crystal structure with Materials Studio software, the corresponding lattice parameters, free energy, chemical bond population bond length were also calculated. The results show that the calcium atom vacancy has a significant effect on the stability of 12CaO？7Al2O3 crystal structure. The lattice parameter and the cell volume decrease while the free energy increases with the increase of calcium atom vacancy in 12CaO？7Al2O3. The main bonds of 12CaO？7Al2O3 of are O—Ca, and the number of O—Ca decreases from 4 to 3, and bond length increase when the calcium vacancy increases to 0.75 and 1.00, resulting in the stability decrease of 12CaO？7Al2O3. The 12CaO？7Al2O3 crystals with calcium atom vacancies of 0, 0.50 and 1.00 were synthesized respectively, and the decomposition rate of 12CaO？7Al2O3 in sodium carbonate solution increases as the calcium vacancy increases, the crystal stability of which is in accordance with the computer simulation results.
Key words: 12CaO？7Al2O3; crystal structure; stability; calcium vacancy; computer simulation
