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J. H. Neave B. A. Joyce P. J. Dobson 《Applied Physics A: Materials Science & Processing》1984,34(3):179-184
Detailed measurements have been made of the specular beam intensity in RHEED patterns from static and growing GaAs surfaces. The basic parameters investigated were substrate temperature and electron beam azimuth. The results have provided further understanding of growth dynamics and surface disorder, respectively. There is a significant trend away from two-dimensional growth at the higher temperatures, which also correspond to more Ga-rich surface structures. Conversely, surface disorder is apparently greater during growth at the lower temperatures, where the structure is As-rich. The static As-stable 2×4 surface is, however, the most ordered and the most closely two-dimensional. It has also been shown that ordered, two-dimensional growth can be initiated from excess Ga adatom populations. 相似文献
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D. D. Joyce 《Inventiones Mathematicae》1996,123(1):507-552
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Harry J.T. Preston Joyce J. Kaufman Jaime Keller J.Bryan Danese John W.D. Connolly 《Chemical physics letters》1976,37(1):55-59
The multiple-scattering Xα model has been applied to the sequence of boron trihalides BX3 where X = F.C1. Br, and I. Transition state calculations show good agreement with the experimental ionization potentials measured by photoelectron spectra. 相似文献
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Reaction of [Mo(CO)4(diene)] with 4,4′-bipyridine (44′B), trans-1,2-bis(2-pyridyl)ethene (2-bpe) and trans-1,2-bis(4-pyridyl)-ethene (4-bpe) gives polymeric [Mo(CO)4(44′B)]n, mononuclear cis-[Mo(CO)4(2-bpe)2] and binuclear [Mo(CO)4(4-bpe)]2 respectively. Reaction of the same ligands with [Mo(CO)4(bpy)] (bpy is 2,2′-bipyridine) produces the bridged binuclear complexes [{Mo(CO)3(bpy)}2(44′B)] and [{Mo(CO)3(bpy)}2(4-bpe)]. Products are characterised by microanalysis and spectroscopy (IR, 1H NMR, UV/vis). Reduction of [{Mo(CO)3(bpy)}2(44′B)] produces an anion in which the unpaired electron is localised on the chelating bpy ligand. 相似文献
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MS -Xα calculations have been performed for the neutral species and the transition states for the positive and negative ions of the heavy metal atoms Mo, W, Re, Ir, Pt, and U and their diatomic hydrides and fluorides. Both nonspin-polarized and spin-polarized calculations were performed. The main purpose of this study was to gain insight into which negative ion species might be preferable to try to prepare for use in ion sources for tandem accelerators. 相似文献
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