【摘要】 本文提出了一个由低能电子衍射能带理论计算所确定的GaAs（111）—（2×2）表面的空位模型。发现第一层间距d₁=0.203±0.005A（收缩75％±0.005A）,第二原子层间距d₂=2.71±0.04A（膨胀11％±0.04A）和第三层间距d₃=0.78±0.02A（收缩4.4％±0.02A）。对此结构,在表面的As—Ga键长l_AS1-Ga₁=2.449±0.001A,As的背键长l_AS1-Ga₂=2.450±0.002A,其键角（α）为120.06°±0.04°,而悬挂键P的角（β）为93.56°±0.03°。更多还原

【Abstract】 In this papar, a Vacancy-model of the GaAs(111) -(2×2) surface determined from band theory of Low-Energy electron diffraction are presented. We found the first-layer distance d1 =0.203±0.005A (contracted 75°±0.005A). the second-layer distance d2 = 2.71±0.04A (expanded 11°±0.04A)i and the third-layer distance d3 = 0.78±0.02A (contracted 4.4°±0.02A). For this structure, the bond length at surface As-Ga lA·1-G·1 = 2.449±0.001 A, the As ack bond length lA:1-G:2 = 2.450±0.002A and an angle of bond (α) of 120.06°±0.04°, and an angle of the P dangling bonds (β) of 93.56°± 0.03°.更多还原