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Bohr method

Units keyword 14, 34 Bohr option 287 Radian option 287 unrestricted methods 10 user initialization files xxxiii... [Pg.302]

Fig. 7. Maps of the electronic charge density in the (110) planes In the ordered twin with (111) APB type displacement. The hatched areas correspond to the charge density higher than 0.03 electrons per cubic Bohr. The charge density differences between two successive contours of the constant charge density are 0.005 electrons per cubic Bohr. Atoms in the two successive (1 10) planes are denoted as Til, All, and T12, A12, respectively, (a) Structure calculated using the Finnis-Sinclair type potential, (b) Structure calculated using the full-potential LMTO method. Fig. 7. Maps of the electronic charge density in the (110) planes In the ordered twin with (111) APB type displacement. The hatched areas correspond to the charge density higher than 0.03 electrons per cubic Bohr. The charge density differences between two successive contours of the constant charge density are 0.005 electrons per cubic Bohr. Atoms in the two successive (1 10) planes are denoted as Til, All, and T12, A12, respectively, (a) Structure calculated using the Finnis-Sinclair type potential, (b) Structure calculated using the full-potential LMTO method.
These ideas were so revolutionary that they would not have been accepted except for the fact that Bohr was able to propose a way to calculate exactly the energy levels for the hydrogen atom. Within ten years Bohr s calculational methods were completely replaced by better techniques, but his postulate that only certain atomic energy states are possible has been repeatedly shown to be correct. [Pg.260]

The mathematical relationship (4) is the one Bohr was able to deduce. Current quantum mechanical methods also deduce this relationship, of course, but with a model that is in fundamental discord with the one used by Bohr. [Pg.261]

PbS has attracted much attention due to its special direct band gap energy (0.4 eV) and a relatively large exciton Bohr radius (18 nm) and their nanoclusters have potential applications in electroluminescent devices such as light-emitting diodes. PbS nanocrystals with rod like structures with diameters of 20-60 nm and lengths of 1-2 pm have been obtained using the sonochemical method and by using PEG-6000 [66]. Addition of PEG and the time of sonication have been found to play a key role in the formation of these rods. [Pg.206]

The IRC in mass-weighted internal coordinates (amu1/2 bohr) is determined by the method of C. Gonzalez and H. B. Schlegel, J. Phys. Chem. 94 (1990), 5523. [Pg.708]

Straight simulation of collision processes relevant to stopping by solution of the classical equations of motion has been common for about two decades [64]. Although the necessary computational effort is considerable, remarkable results have been found in comparisons with experimental results such as emitted-electron spectra [65]. The main application area of this method refers to very heavy ions at not too high speeds where the Bohr criterion is well satisfied yet relativistic effects are insignificant. [Pg.107]

The discovery of the rare earth elements provide a long history of almost two hundred years of trial and error in the claims of element discovery starting before the time of Dalton s theory of the atom and determination of atomic weight values, Mendeleev s periodic table, the advent of optical spectroscopy, Bohr s theory of the electronic structure of atoms and Moseley s x-ray detection method for atomic number determination. The fact that the similarity in the chemical properties of the rare earth elements make them especially difficult to chemically isolate led to a situation where many mixtures of elements were being mistaken for elemental species. As a result, atomic weight values were not nearly as useful because the lack of separation meant that additional elements would still be present within an oxide and lead to inaccurate atomic weight values. Very pure rare earth samples did not become a reality until the mid twentieth century. [Pg.3]

When Bohr published his first paper on the topic in 1921, the physicists who read it were convinced that his results were based on undisclosed calculations. They didn t see how so complex a theory could be worked out without making use of some mathematical foundation. But they were wrong. Bohr often proceeded intuitively, using whatever principle seemed most appropriate, as he considered one or another of the elements. Given his methods, it isn t surprising that Bohr made some faulty assignments. Nevertheless, his picture of atomic structure is basically the same as the one used by chemists and physicists today. [Pg.192]

Two dynamic methods have been developed for measurement of the surface tensions, the method of ripples first employed by Rayleigh and the vibrating jet method developed by Bohr. [Pg.16]

Rc-h = Re = 2.13713 bohr with the CR-EOMCCSD(T) approach, with the analogous results obtained in the EOMCCSD, CC3, EOMCCSDT, and full Cl calculations reported in Refs. [39,44,103] is given in Table 2. As one can see, the relatively inexpensive CR-EOMCCSD(T) method, which has the ease-of-use of the standard ground-state CCSD(T) approach, pro-... [Pg.85]

The CR-EOMCCSD(T) sf method is currently under development, so that we cannot show too many examples of the actual applications yet. However, we have already tested the CR-EOMCCSD(T) approach using the electronic excitations in the CH+ ion as an example. The CR-EOMCCSD(T)j > results for the three lowest-energy excited states of the symmetry and two lowest-energy states of the H and symmetries, obtained at the equilibrium geometry Rc-h = Re = 2.13713 bohr and the same [5s3pld/3slp] basis set of Ref. [103] as used in the MMCC(2,3)/CI, MMCC(2,3)/PT, and CR-EOMCCSD(T) calculations discussed in Section 3.1, are shown in Table 2. As one can see, the CR-EOMCCSD(T) 5f approach is as effective in improving the EOMCCSD results as the CR-EOMCCSD(T) method analyzed in Section 3.1.2. This is particularly true for the 2 1 A, and 2 A states that are dominated by double exci-... [Pg.99]


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See also in sourсe #XX -- [ Pg.4 , Pg.5 ]




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