(1. 哈爾濱工業(yè)大學(xué) 材料科學(xué)與工程學(xué)院，哈爾濱 150001；2. 吉林大學(xué) 理論化學(xué)計算國家重點實驗室，長春 130023)
摘 要:
關(guān)鍵字: 鈦－氫體系；第一原理；晶體結(jié)構(gòu)；結(jié)合能；溶解熱
（1. School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China;2. State Key Laboratory of Theoretical and Computational Chemistry, Jilin University, Changchun 130023, China）
Abstract:The equilibrium structures and total energies of α-Ti-H and β-Ti-H crystals with different mole ratios of Ti to H were calculated with the first-principles method based on plane-wave pseudopotential and density function theory. The calculated results show that hydrogen causes the lattice distortion and volume expansion of α-Ti and β-Ti crystals. The calculated binding energies of α-Ti-H and β-Ti-H crystals with different mole ratios of Ti to H are less than those of pure α-Ti and β-Ti crystals, respectively. It reveals that hydrogen atom reduces the binding energies of α-Ti and β-Ti crystals. The calculation results show that the site preference of hydrogen in β-Ti crystal varies with hydrogen content varyiing. Hydrogen is inclined to enter the tetrahedral interstitial site in β-Ti-H crystal with low hydrogen content, and hydrogen is disposed to occupy the octahedral site in β-Ti-H crystal with high hydrogen content.
Key words: Ti-H system; first-principles; crystal structure; binding energy; solution heat
