Photoelectron spectra of Nbn− clusters: Correlation between electronic structure and hydrogen chemisorption

Abstract

Photoelectron spectra of mass-separated Nb n Ϫ clusters reveal an even/odd alternation for nϭ6-17, indicating a closed electronic shell of the neutral even-numbered clusters. The HOMO-LUMO gap of Nb 8 , Nb 10 , and Nb 16 is found to be larger than that of the other even-numbered clusters, which correlates with the low H 2 reactivities of these species. The spectrum of Nb 15 Ϫ is different from all other clusters in this size range, which might be an indication for a geometric bcc shell closing. The influen e of the electronic structure of the clusters on the reactivity is discussed.

The far-infrared spectra of neutral and cationic niobium clusters: Nb5∕+ to Nb9∕+

“…Partly because of their relative ease of production and the favorable isotopic distribution, niobium clusters have been intensively investigated experimentally and this has been followed by extensive theoretical studies. Experimental studies include single and multiphoton ionizations, [13][14][15][16] as well as photoelectron spectroscopy [17][18][19][20] and the measurements of the bond dissociation energies. 21,22 Optical absorption spectra of neutral niobium clusters have been measured by means of photodissociation of their complexes with rare-gas atoms [23][24][25] and this technique is also used here for obtaining the vibrational spectra.…”

Soft landing of size-selected clusters in rare gas matrices

“…Clusters of atoms or molecules are fascinating objects to study the evolution of electronic [1][2][3], magnetic [4][5][6][7] or chemical [8][9][10] properties from isolated atoms to bulk matter. Many types of cluster sources [11][12][13][14] have been developed and adapted to investigate a wide range of physical phenomena [15,16].…”

Thermochemistry of Hydrocarbon Radicals

“…We primarily rely on electron affinity measurements obtained by a number of excellent groups doing negative ion photoelectron spectroscopy. [35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50] We have also collaborated with Prof. W. Carl Lineberger at the University of Colorado, Boulder, on negative ion photoelectron spectra of systems of relevance to combustion kinetics. During a sabbatical visit by the PI in Boulder, we obtained spectra of the napthide anion, C 10 H 7 !…”