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71.
The results of a photoelectron study using ultraviolet 40.81 eV photons (UPS) of the outermost bands of the molecular solids NH3 and H2O are reported. The binding energies, the energy separation, the band widths and the branching ratio of the two outermost bands of solid NH3 are found not to be significantly different from the 3al and 1e molecular orbital states of the gaseous NH3 UPS spectrum. This implies that hydrogen bonding has not produced any significant change in the electronic structure of the valence bands of solid NH3. Because of a much smaller intermolecular hydrogen bond length in solid H2O compared to that in solid NH3, the hydrogen bond does, however, produce a significant change in the valence bands of H2O on solidification, and because of the orbital geometry it predominantly affects the 3al molecular orbital state.  相似文献   
72.
A photoelectron study of the outermost bands of solid-phase SnCl2 and SnBr2 using 40.81 eV photons is reported. The main features of the spectra are successfully interpreted in terms of molecular orbital theory for the appropriate isolated molecules.  相似文献   
73.
MP matrices are those real matrices which possess a nonnegative, nonsingular l-inverse. This paper characterizes the nonnegative MP matrices and hence, determines when a nonnegative matrix A has a convergent regular splitting MQ which induces the linear stationary iterative scheme xk+1=M-1Qxk+M-1b to solve Ax=b.  相似文献   
74.
Anomalous line-broadening in the paramagnetic resonance of FeF3 · 3H2O, which has a linear chain arrangement, has been observed. The line width was found to decrease monotonically with increasing temperature in the range from 100–300°K.  相似文献   
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77.
We study the breakdown of the Stokes-Einstein (SE) and Debye-Stokes-Einstein (DSE) relations for translational and rotational motion in a prototypical model of a network-forming liquid, the ST2 model of water. We find that the emergence of fractional SE and DSE relations at low temperature is ubiquitous in this system, with exponents that vary little over a range of distinct physical regimes. We also show that the same fractional SE relation is obeyed by both mobile and immobile dynamical heterogeneities of the liquid.  相似文献   
78.
We report the first observations of spinodal decomposition in solid helium isotopic mixtures, using NMR measurements. The experiments were performed at a 3He concentration of 50% where the transition proceeds through the critical point. We used an initial pressure such that the system remained solid. Our observations indicate that the transition occurs by the mechanism of spinodal decomposition and we are able to study its evolution in real time.  相似文献   
79.
Liu J  Lu Z  Raymond S  Poole PJ  Barrios PJ  Poitras D 《Optics letters》2008,33(15):1702-1704
We report on the generation of dual-wavelength self-mode-locking pulses from an InP-based quantum dot laser. The demonstrated device operates simultaneously at both 1543.7 and 1571.7 nm and has a repetition rate of 92.5 GHz. The pulse width is below 960 fs, and the average power coupled to a cleaved single-mode fiber is nearly 9 mW at a current bias of 60 mA.  相似文献   
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