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71.
Chakrabarti D Totton TS Kraft M Wales DJ 《Physical chemistry chemical physics : PCCP》2011,13(48):21362-21366
We report on a survey of the potential energy surface for the 13-molecule benzene cluster, (C(6)H(6))(13), bound by an atom-atom intermolecular potential developed from first principles. The potential, which has an anisotropic repulsion term, is found to support distinct pairs of structures of C(3), C(i), and S(6) symmetry as low-lying minima, including a C(3) global minimum. The organisation of the low-lying region of the potential energy surface suggests that one of the S(6) structures is likely to act as a kinetic trap, hindering efficient relaxation to the global minimum, in agreement with the hypothesis that two isomers coexist in this system, suggested by spectroscopic experiments. 相似文献
72.
A. Chatterjee B. K. Chakrabarti 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,54(3):399-404
We study here numerically the behavior of an ideal gas like model of markets having
only one non-consumable commodity. We investigate the behavior of the
steady-state distributions of money, commodity and total wealth,
as the dynamics of trading or exchange of money and commodity proceeds,
with local (in time) fluctuations in the price of the commodity.
These distributions are studied in markets with agents having uniform and
random saving factors. The self-organizing features in money distribution
are similar to the cases without any commodity (or with consumable
commodities), while the commodity distribution shows an exponential decay.
The wealth distribution shows interesting behavior: gamma like
distribution for uniform saving propensity and has the same power-law tail,
as that of the money distribution, for
a market with agents having random saving propensity. 相似文献
73.
A simplified analysis is employed to handle a class of singular integro-differential equations for their solutions 相似文献
74.
L.A. Farina X. Bai . Kurdak S. Chakrabarti P. Bhattacharya M.Shayegan 《Physica E: Low-dimensional Systems and Nanostructures》2006,34(1-2):187
We have fabricated devices on GaAs/AlGaAs heterostructures, containing two-dimensional electron gases, that consist of three point contacts surrounding an etched antidot with an Al/AlOx/Al single electron transistor. The single electron transistor measurement shows rearrangement of neighboring charged impurities with a characteristic stability time scale of 20 s in one device and greater than 1 h in a second device. We also measured the resistance of the point contact–antidot constriction versus magnetic field. In a device with a 20 s stability time, we see a high noise level and poor reproducibility. In a device with a long stability time, much greater than 1 h, we are able to see reproducible features including Aharonov–Bohm oscillations. 相似文献
75.
P. Chakrabarti S. C. Choudhury B. B. Pal 《Applied Physics A: Materials Science & Processing》1989,48(4):331-334
The noise generated due to randomness of multiplication process in the avalanche region of an Al
x
Ga1–x
As/GaAs quantum well p+-i-n+ structure has been studied. The paper presents a quantitative evaluation of the noise performance of the superlattice APD which has not been done so far. Further, useful design data for low noise structure is given. 相似文献
76.
77.
78.
79.
A direct method of solution is presented for singular integral equations of the first kind, involving the combination of a logarithmic and a Cauchy type singularity. Two typical cases are considered, in one of which the range of integration is a single finite interval and, in the other, the range of integration is a union of disjoint finite intervals. More such general equations associated with a finite number (greater than two) of finite, disjoint, intervals can also be handled by the technique employed here. 相似文献
80.
C. G. Chakrabarti 《Zeitschrift für Physik B Condensed Matter》1985,61(3):353-355
The paper deals with the study of Gibbs entropy and the properties of mixing character and mixing of phases in the course grained interpretation of irreversible approach to statistical equilibrium of an isolated system. 相似文献