中文摘要：

采用密度泛函理论中的广义梯度近似方法（GGA）对RTH结构分子筛的酸性进行了研究。考察了4个不同T位的Al的替代能以及16个不同Br nsted酸位的脱质子能,从而推断可能的Al的取代位以及不同酸位的酸性强弱。结果表明,RTH结构分子筛上最有可能的Al的取代位为T4,位于八元环的孔口（0.56 nm×0.25 nm）;从结构和酸性考虑,易与反应物接触且酸性较强的Br nsted酸位点在Al4-O9（H）-Si2和Al4-O16（H）-Si4上,并且这两个酸位点都指向两个八元环孔口。

英文摘要：

The acidity of zeolite with RTH structure had been studied using the density functional theory generalized gradient approximation（GGA） method for the first time.The Al substitution energy of four different T sites and the deprotonation energies of sixteen different Brnsted acid sites were calculated to found the preferred Al substitution energy and acidic strength of different B acid sites.The results show that T4,locating in the opening（0.56 nm×0.25 nm） of 8-membered ring,is the most favorable T site for Al substitution in the RTH structure.With considerations on both structure and acidity,Al4-O9（H）-Si2 and Al4-O16（H）-Si4,locating in the intersection part of the two 8-membered ring channel,show stronger Brnsted acidity and are the most possible active sites for acid catalytic reaction.