摘要
超卤素团簇特殊的稳定性和物理化学性质使得它特别适合作为制造新型团簇组装型材料的基元.BO2团簇的电子亲和能达到了4.46eV,同时它的中性团簇差一个电子达到满壳层,具备了成为超卤素的条件.采用光电子能谱与密度泛函理论计算相结合的方法,研究了BO2与Na,Cu原子的相互作用,以及所形成的NaBO2团簇的水溶性.结果表明,在BO2与Na,Cu原子相互作用所形成的CuBO2和NaBO2团簇中,BO2仍然保持直线型结构并且表现出与卤素相似的性质,所形成团簇的电子特性也与卤盐类似.另一方面,NaBO2团簇的水溶性也与卤盐的溶解特性一致,刚开始以紧密离子对(CIP)形式存在,在结合了3个水分子以后,光电子能谱有了很明显的改变,对应着Na+与(OBO)-的溶剂隔离的离子对结构(SSIP)的出现.并且,在实验过程中,还出现了电子亲和能更大的Cu(BO2)2团簇(5.07eV),为了与超卤素相区别,我们定义其为长链二级超卤素,该团簇由3种元素组成,使得人们将其用于团簇组装型材料的制备过程时有了更大的自由度.
Superhalogens exhibit special stable characters and electronic properties, and are suitable to De used as building blocks in designing cluster assembling materials. BO2 is only one electron short to electronic shell closing and has a high electron affinity, 4.46 eV, larger than that of halogen atoms, so BO2 can be considered as a superhalogen. In order to confirm this, the interactions between BO2 and Cu, Na atoms as well as microscopic salvation of NaBOz cluster were intensively studied through anionphotoelectron spectroscopy （PES） and density functional theory （DFT） calculatlon. I he studms show mat BO2 moiety still retains its linear structure as the bare BOz cluster and behaves as a superhalogen. On the other hand, the microscopic solvation of NaBO2 in water is similar to that of halogen salts. NaBO2 appears as contact ion pair （CIP） structure at first, and then there is a significant change in the photoelectron spectra of NaBO2- （HaO）n clusters starting from n= 3, corresponding to the transition from contact ion pair （CIP） structure to solvent-separated ion pair （SSIP） structure. Besides, with an electron affinity of 5.07 eV, which is larger than that of its BO2 superhalogen building-block, Cu（BO2）2 can be classified as a hyperhalogen. Since the hyperhalogen contains three different elements, it has much more freedom in designing materials.
基金
国家自然科学基金青年科学基金(21201052)
安徽高校自然科学研究重点项目(KJ2013A224)
合肥师范学院人才科研启动基金(2012rcjj01)资助
关键词
负离子光电子能谱
密度泛函
超卤素
团簇组装型材料
anion photoelectron spectroscopy density functional theory superhalogens cluster-assemblematerials
