用从头计算Hartree-Fock方法研究了MoO3(010)和(100)晶面上几种结构不等价氧的成键特征和电子结构,并考察了H+在不同氧位上的吸附性能以及吸附后形成的OH从表面脱附的性质.结果表明,在氧化钼晶体中,钼氧原子间的成键具有离子性和共价性相结合的特性,且几种不等价氧与钼之间的成键性质各不相同:端氧或不对称桥氧与钼的成键具有较强的共价性,而对称桥氧具有较强的离子性;H+在MoO3(010)和(100)晶面上几种不等价氧位都能形成稳定的吸附,而在端氧位的吸附最稳定;H+吸附形成的OH都与表面有较强的作用,端氧位的OH最难脱附,而桥氧位的OH在表面的活动性较大,故桥氧位很可能是丙烯选择氧化过程中脱氢反应的活性中心.
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