Another realistic approach is to constnict pseiidopotentials using density fiinctional tlieory. The implementation of the Kolm-Sham equations to condensed matter phases without the pseiidopotential approximation is not easy owing to the dramatic span in length scales of the wavefimction and the energy range of the eigenvalues. The pseiidopotential eliminates this problem by removing tlie core electrons from the problem and results in a much sunpler problem [27]. [Pg.110]

The value of at zero temperature can be estimated from the electron density ( equation Al.3.26). Typical values of the Femii energy range from about 1.6 eV for Cs to 14.1 eV for Be. In temis of temperature (Jp = p//r), the range is approxunately 2000-16,000 K. As a consequence, the Femii energy is a very weak ftuiction of temperature under ambient conditions. The electronic contribution to the heat capacity, C, can be detemiined from... [Pg.128]

Typically, the ratio of this to the incident flux detennines the transition probability. This infonnation will be averaged over the energy range of the initial wavepacket, unless one wants to project out specific energies from the solution. This projection procedure is accomplished using the following expression for the energy resolved (tune-independent) wavefunction in tenns in tenns of its time-dependent counterpart ... [Pg.981]

Hold U, Lenzer T, Luther K, Reihs K and Symonds A C 2000 Collisional energy transfer probabilities of highly excited molecules from kinetically controlled selective ionization (KCSI). I. The KCSI technique experimental approach for the determination of P(E, E) in the quasicontinuous energy ranged. Chem. Phys. 112 4076-89... [Pg.1086]

electronic transitions at several electron volts. EELS spectrometers have to satisfy a number of stringent requirements. First, the primary electrons should be monochromatic. Second,... [Pg.1865]

As an indication of the types of infonnation gleaned from all-electron methods, we focus on one recent approach, the FLAPW method. It has been used to detennine the band stmcture and optical properties over a wide energy range for a variety of crystal stmctures and chemical compositions ranging from elementary metals [ ] to complex oxides [M], layered dichalcogenides [, and nanoporous semiconductors The k p fonnulation has also enabled calculation of the complex band stmcture of the A1 (100) surface... [Pg.2214]

Wang M-X, Keller J, Boulmer J and Weiner J 1987 Spin-seleoted velooity dependenoe of the assooiative ionization oross seotion in Na(3p) + Na(3p) oollisions over the oollision energy range from 2.4 to 290 meV Phys.Rev. A 35 934-7... [Pg.2481]

Figure 5. Variation of n ace(u) with scaled energy, E/htii, derived from Eq. (A.13) with Eq — 0.5/t j>, The Roquet bands in Figure cover energy ranges such that trace( ) < 2. |

One should also note that the unfolding procedure makes the average density of levels unifomi over the entire energy range. Thus, the difference... [Pg.601]

In large systems there can be many orbitals in a small energy range, and the size of the Cl matrix can be very sensitive to the value of the maximum excitation if you use Biergy Criterion. Since calculation time depends heavily on the size of the Cl matrix, you can end up with very long calculations, especially if you use the ab initio methods or the MNDO, AMI, or PM3 semi-empirical methods. This could exhaust the memory of your system. Again, inspecting the results of an RHF (no Cl) calculation will help you avoid these pitfalls. [Pg.40]

An approximate measure of the projected range can be found using LSS theory (8) for ions in the energy range where nuclear stopping dominates... [Pg.393]

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