中文摘要：

采用基于密度泛函理论（DFT）的广义梯度近似（GGA）／PBE（Perdew．Burke．Ernzerhof）交换相关泛函和双数值基加P极化（DNP）基组对氢气分子在Na—MAZ和Li-MAZ沸石原子簇上的吸附进行了研究，计算得到吸附复合物的平衡几何结构参数、振动频率以及吸附能等数据．结果表明：MAZ沸石中存在四个稳定的吸附位点，分别为SI′、SI″、SII′和SII″位点；氢气分子在Na—MAZ沸石的SfI啦点吸附时最稳定，而在Li—MAZ沸石中。氢气分子处于Sl″和SII″位点时最稳定．吸附能越大，氢气分子键长越长，振动频率减少也越多．Li-MAZ沸石对氢气的吸附能力要明显强于Na-MAZ沸石的吸附能力，理论上Li—MAZ沸石具有更高的氢气储量，可能是一种潜在的储氢材料．

英文摘要：

Hydrogen adsorption on zeolite Na-MAZ and Li-MAZ clusters was investigated using density functional theory （DFT） with the generalized gradient approximation （GGA） of the Perdew-Burke- Ernzerhof （PBE） exchange-correction functional and the double numerical plus polarization （DNP） basis set. Equilibrium structural parameters, vibration frequencies, and adsorption energies were obtained and compared. The calculated results show that four stable adsorption sites are present on zeolite MAZ. They are designated SI＇, SI＂, SII＇, and SII＂, respectively. The most stable adsorption structure was hydrogen on the SII＂ site of zeolite Na-MAZ and the hydrogen on the SI＂ and SII＂ sites of zeolite Li-MAZ were the most stable. We also found that larger adsorption energies indicate longer H-- H bond distances and a lower vibration frequency shift. The adsorption ability of zeolite Li-MAZ toward hydrogen is stronger than that of zeolite Na-MAZ. Zeolite Li-MAZ has a higher theoretical hydrogen storage capacity and it may be a potential hydrogen storage material.