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91.
92.
93.
Mass spectrometry and photoelectron spectroscopy of o-, m-, and p-terphenyl cluster anions, (o-TP)n(-) (n = 2-100), (m-TP)n(-) (n = 2-100), and (p-TP)n(-) (n = 1-100), respectively, are conducted to investigate the effect of molecular shape on the molecular aggregation form and the resultant ion core character of the clusters. For (o-TP)n(-) and (m-TP)n(-), neither magic numbers nor discernible isomers are observed throughout the size range. Furthermore, their vertical detachment energies (VDEs) increase up to large n and depend linearly on n(-1/3), implying that they possess a three-dimensional (3D), highly reorganized structure encompassing a monomeric anion core. For (p-TP)n(-), in contrast, prominent magic numbers of n = 5, 7, 10, 12, and 14 are observed, and the VDEs show pronounced irregular shifts below n = 10, while they remain constant above n = 14 (isomer A). These results can be rationalized with two-dimensional (2D) orderings of p-TP molecules and different types of 2D shell closure at n = 7 and 14, the monomeric and multimeric anion core, respectively. Above n = 16, the new feature (isomer B) starts to appear at the higher binding side of isomer A, and it becomes dominant with n, while isomer A gradually disappears for larger sizes. In contrast to isomer A, the VDEs of isomer B continuously increase with the cluster size. This characteristic size evolution suggests that the transition to modified 2D aggregation forms from 2D ones occurs at around n = 20. 相似文献
94.
We demonstrate the formation of nanoscale volcano-like structures induced by ion-beam irradiation of nanoscale pores in freestanding silicon nitride membranes. Accreted matter is delivered to the volcanoes from micrometer distances along the surface. Volcano formation accompanies nanopore shrinking and depends on geometrical factors and the presence of a conducting layer on the membrane's back surface. We argue that surface electric fields play an important role in accounting for the experimental observations. 相似文献
95.
The diffusion and interactions of CO molecules on Pd(111) were studied by scanning tunneling microscopy. By following the random walk motion of individual molecules as a function of temperature, an activation energy barrier for diffusion of 118 +/- 5 meV was determined. The interaction between CO molecules was found to be repulsive for pairs separated by one or two Pd(111) lattice distances, and weakly attractive at a separation of sqrt[3]. 相似文献
96.
Cerdá J Michaelides A Bocquet ML Feibelman PJ Mitsui T Rose M Fomin E Salmeron M 《Physical review letters》2004,93(11):116101
Scanning tunneling microscopy (STM) images of water submonolayers on Pd(111) reveal quasiperiodic and isolated adclusters with internal structure that would ordinarily be ascribed to icelike puckered hexagonal units. However, density functional theory and STM simulations contradict this conventional picture, showing instead that the water adlayers are composed mainly of flat-lying molecules arranged in planar water hexagons. A new rule for two dimensional (2D) water growth is offered that generates the structures observed experimentally from planar hexamer units. 相似文献
97.
Eguchi K Enomoto S Furuno K Ikeda H Ikeda K Inoue K Ishihara K Iwamoto T Kawashima T Kishimoto Y Koga M Koseki Y Maeda T Mitsui T Motoki M Nakajima K Ogawa H Owada K Piquemal F Shimizu I Shirai J Suekane F Suzuki A Tada K Tajima O Takayama T Tamae K Watanabe H Busenitz J Djurcic Z McKinny K Mei DM Piepke A Yakushev E Berger BE Chan YD Decowski MP Dwyer DA Freedman SJ Fu Y Fujikawa BK Goldman J Heeger KM Lesko KT Luk KB Murayama H Nygren DR Okada CE Poon AW Steiner HM Winslow LA Horton-Smith GA 《Physical review letters》2004,92(7):071301
Data corresponding to a KamLAND detector exposure of 0.28 kton yr has been used to search for nu;(e)'s in the energy range 8.3相似文献
98.
Seto M Kitao S Kobayashi Y Haruki R Yoda Y Mitsui T Ishikawa T 《Physical review letters》2003,91(18):185505
We have performed the measurement of the site-specific phonon densities of states (PDOS) discerned using electronic states. As far as we know, no general method could give the site-specific PDOS, although oscillating properties of the individual atoms in nonequivalent positions are not necessarily equivalent. However, the combination of the energy and time domain measurements of the nuclear resonant scattering of synchrotron radiation allows the identification of site-specific PDOS. We measured the site-specific PDOS of iron atoms in magnetite, which is a mixed valent compound, and the difference between partial phonon densities of the iron sites was clearly observed. 相似文献
99.
S. Kawabata N. Ishikawa M. Mitsui A. Nakajima 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,43(1-3):155-158
Uniform-sized silver nanoparticles with average diameter of 13.7 nm have been prepared in the gas-phase by combining a pulsed
laser ablation method
with a low pressure-differential mobility analyzer (LP-DMA). By depositing
the silver nanoparticles onto a silicon substrate, a granular film
consisting of size-selected silver nanoparticles has been fabricated and its
morphology and electronic properties have been examined using transmission
electron microscopy (TEM) and UV-visible absorption spectroscopy. This
granular silver film serves as a highly active substrate for
surface-enhanced Raman scattering (SERS). 相似文献
100.
Yoshihiko Shoji Takao Asaka Hideki Dewa Hirohumi Hanaki Yoshinori Hisaoka Toshiaki Kobayashi Takahiro Matsubara Takayuki Mitsui Akihiko Mizuno Shinsuke Suzuki Tsutomu Taniuchi Hiromitsu Tomizawa Kenichi Yanagida 《Infrared Physics & Technology》2008,51(5):394-396
We have demonstrated the idea of circulating a short, intense linac bunch for some tens of turns in an isochronous ring. We compressed a bunch from the SPring-8 linac to a few picoseconds rms by means of an energy compression system and a beam transport line from the linac to NewSUBARU. The NewSUBARU storage ring was set to a quasi-isochronous condition and the bunch circulated for about 50 turns after injection while maintaining the short bunch length. At the same time, a pulse train of strong coherent synchrotron oscillation from the short bunch was observed. 相似文献