An ab initio density functional study was performed investigating the adsorption of CO 2 on the neutral boron B n (n = 10 − 13) clusters, characterized by planar and quasiplanar ground-state atomic structures. For all four clusters, we found strong chemisorption energy of CO 2 reaching 1.6 eV for B 12 at the cluster edge sites with the adsorbed molecule in the plane of the cluster.A configuration with chemisorbed dissociated CO 2 molecule also exists for B 11 and B 13 clusters.The strong adsorption is due to the bending of the CO 2 molecule, which provides energetically accessible fully in-plane frontier molecular orbitals matching the edge states of the clusters. At the same time, the intrinsic dipole moment of a bent CO 2 molecule facilitates the transfer of excess electronic charge from the cluster edges to the molecule.

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a b s t r a c tRoom-temperature amplified spontaneous emission (ASE) has been observed from aqueous chemical grown zinc oxide (ZnO) microrods. The well-faceted microrods have only a single narrow ultraviolet (UV) emission at 390 nm (3.2 eV) with average lifetimes as fast as 85-100 ps. The characteristic ASE also exhibits blue-shifted peaks and shortened lifetimes. At present, the peak shifting and the lifetime shortening are attributed to the band filling and photo-induced screening effects and to the nonradiative relaxation process, respectively. Results indicate that the ZnO microrods have good structural and optical quality which leads to their suitable use for optoelectronic applications.