scholarly journals Theoretical investigation of the single and double ionization spectra of M(CO)6, M=W

2020 ◽  
Vol 2 (4) ◽  
Author(s):  
Behnam Nikoobakht ◽  
◽  
Gulzari L. Malli ◽  
Martin Siegert
Keyword(s):  
Electronic Structures ◽  
Fock Space ◽  
Double Ionization ◽  
Ionization Potentials ◽  
Final State ◽  
Molecular Systems ◽  
Consistent Treatment ◽  
Cluster Methods ◽  
Theoretical Considerations ◽  
Good Agreement

In this work, we study the single and double ionization spectra of the M(CO)6,with M =( W and Cr ) complexes by applying the four-component algebraic diagrammatic construction and Fock-space coupled cluster methods to extend earlier studies based on less demanding approaches. The computed single and double ionization potentials are in good agreement comparing with the available experimental results. The electronic structures of the cationic molecular systems are carefully investigated by computing accurately single and double ionization potentials. The final state characterization is relied on group theoretical considerations of the contributing orbitals and allowed for a clear assignment. Energy level diagrams show the effect of spin-orbit (SO) coupling starting from scalar relativistic results and for the heavy representative M(CO)6 with M =( W and Cr ) nonadditivity effects of the SO and electron correlation can be observed requiring a consistent treatment of both contributions.

scholarly journals EVENTS WITH ISOLATED CHARGED LEPTONS AND LARGE MISSING TRANSVERSE MOMENTUM AT HERA

2004 ◽  
Vol 19 (25) ◽  
pp. 1881-1902 ◽  
Author(s):  
TANCREDI CARLI ◽  
DOMINIK DANNHEIM ◽  
LORENZO BELLAGAMBA
Keyword(s):  
Transverse Momentum ◽  
Zeus Collaboration ◽  
Tau Leptons ◽  
High Luminosity ◽  
Final State ◽  
Missing Transverse Momentum ◽  
State Formula ◽  
Charged Leptons ◽  
Good Agreement ◽  
Event Topology

Striking events with isolated charged leptons, large missing transverse momentum and large transverse momentum of the hadronic final state [Formula: see text] were observed at the electron proton collider HERA in a data sample corresponding to an integrated luminosity of about 130 pb-1. The H1 collaboration observed 11 events with isolated electrons or muons and with [Formula: see text]. Only 3.4±0.6 events were expected from Standard Model (SM) processes. Six of these events have [Formula: see text], while 1.3±0.3 events were expected. The ZEUS collaboration observed good agreement with the SM. However, ZEUS found two events with a similar event topology, but tau leptons instead of electrons or muons in the final state. Only 0.2±0.05 events were expected from SM processes. For various hypotheses, the compatibility of the experimental results was investigated with respect to the SM and with respect to possible explanations beyond the SM. Prospects for the high-luminosity HERA-II data taking period are given.

Locality and nonlocality of electronic structures of molecular systems: Toward QM/MM and QM/QM approaches

2012 ◽  
Author(s):  
Shusuke Yamanaka ◽  
Yasushige Yonezawa ◽  
Kazuto Nakata ◽  
Satomichi Nishihara ◽  
Mitsutaka Okumura ◽  
...  
Keyword(s):  
Electronic Structures ◽  
Molecular Systems

scholarly journals Electron-impact double ionization of the carbon atom

2018 ◽  
Vol 620 ◽  
pp. A188 ◽  
Author(s):  
Valdas Jonauskas
Keyword(s):  
Carbon Atom ◽  
Electron Impact ◽  
Cross Sections ◽  
Double Ionization ◽  
Impact Excitation ◽  
Rate Coefficients ◽  
Electron Impact Excitation ◽  
Ionization Cross ◽  
Ionization Cross Sections ◽  
Good Agreement

Electron-impact single- and double-ionization cross sections and Maxwellian rate coefficients are presented for the carbon atom. Scaling factors are introduced for the electron-impact excitation and ionization cross sections obtained in the distorted wave (DW) approximation. It is shown that the scaled DW cross sections provide good agreement with measurements for the single ionization of the C atom and C1+ ion. The direct double-ionization (DDI) process is studied using a multi-step approach. Ionization–ionization, excitation–ionization–ionization, and ionization–excitation–ionization branches are analyzed. It is demonstrated that the three-step processes contribute ≼40% of the total DDI cross sections for the case where one of the electrons takes all of the excess energy after the first ionization process.

Indirect estimation of body surface area and volume

1959 ◽  
Vol 14 (6) ◽  
pp. 1000-1004 ◽  
Author(s):  
Julius Sendroy ◽  
Louis P. Cecchini
Keyword(s):  
Surface Area ◽  
Body Surface Area ◽  
Body Surface ◽  
Body Volume ◽  
Human Beings ◽  
Volume Comparison ◽  
Additional Support ◽  
Human Body Surface ◽  
Theoretical Considerations ◽  
Good Agreement

A convenient and rapid photographic technique of obtaining data which can be used for the calculation of human body surface area is described. The results, which are in good agreement with values obtained by a reliable method of readings from a chart, provide additional support for the application of the increasingly important photographic method of quantitation in human biology. Data have also been obtained which suggest that the surface area of dogs may satisfactorily be estimated by the same previously reported chart method used for human beings. Empirical equations for the calculation of body volume (and density) in man, based essentially on measurements of weight and height, have been developed and tested in respect to measured values obtainable from the literature. Statistical evaluation and the criteria of convenience and rapidity in use, rather than more restrictive theoretical considerations, indicate the superiority of predominantly empirical relationships as the methods of choice for the prediction of body volume. Comparison of the reliability of the results with those obtainable by established methods of quantitation indicates that these equations may be useful as approximate, but most convenient indices of gross body composition. Submitted on April 1, 1959

Modeling Hydroplaning and Effects of Pavement Microtexture

2005 ◽  
Vol 1905 (1) ◽  
pp. 166-176 ◽  
Author(s):  
G. P. Ong ◽  
T. F. Fwa ◽  
J. Guo
Keyword(s):  
Three Dimensional ◽  
Flow Simulation ◽  
Experimental Results ◽  
Tire Pressure ◽  
Finite Volume Model ◽  
Proposed Model ◽  
Loss Of Contact ◽  
The One ◽  
Theoretical Considerations ◽  
Good Agreement

Hydroplaning on wet pavement occurs when a vehicle reaches a critical speed and causes a loss of contact between its tires and the pavement surface. This paper presents the development of a three-dimensional finite volume model that simulates the hydroplaning phenomenon. The theoretical considerations of the flow simulation model are described. The simulation results are in good agreement with the experimental results in the literature and with those obtained by the well-known hydroplaning equation of the National Aeronautics and Space Administration (NASA). The tire pressure–hydroplaning speed relationship predicted by the model is found to match well the one obtained with the NASA hydroplaning equation. Analyses of the results of the present study indicate that pavement microtexture in the 0.2- to 0.5-mm range can delay hydroplaning (i.e., raise the speed at which hydroplaning occurs). The paper also shows that the NASA hydroplaning equation provides a conservative estimate of the hydroplaning speed. The analyses in the present study indicate that when the microtexture of the pavement is considered, the hydroplaning speed predicted by the proposed model deviates from the speed predicted by the smooth surface relationship represented by the NASA hydroplaning equation. The discrepancies in hydroplaning speed are about 1% for a 0.1-mm microtexture depth and 22% for a 0.5-mm microtexture depth. The validity of the proposed model was verified by a check of the computed friction coefficient against the experimental results reported in the literature for pavement surfaces with known microtexture depths.

scholarly journals Shannon, Rényi, Tsallis Entropies and Onicescu Information Energy for Low-Lying Singly Excited States of Helium

Atoms ◽  
2019 ◽  
Vol 7 (3) ◽  
pp. 70 ◽  
Author(s):  
Jen-Hao Ou ◽  
Yew Kam Ho
Keyword(s):  
Excited States ◽  
Shannon Entropy ◽  
Electronic Structures ◽  
Tsallis Entropy ◽  
Renyi Entropy ◽  
Rényi Entropy ◽  
Electron Delocalization ◽  
Information Theoretic ◽  
Molecular Systems ◽  
Information Energy

Knowledge of the electronic structures of atomic and molecular systems deepens our understanding of the desired system. In particular, several information-theoretic quantities, such as Shannon entropy, have been applied to quantify the extent of electron delocalization for the ground state of various systems. To explore excited states, we calculated Shannon entropy and two of its one-parameter generalizations, Rényi entropy of order α and Tsallis entropy of order α , and Onicescu Information Energy of order α for four low-lying singly excited states (1s2s 1 S e , 1s2s 3 S e , 1s3s 1 S e , and 1s3s 3 S e states) of helium. This paper compares the behavior of these three quantities of order 0.5 to 9 for the ground and four excited states. We found that, generally, a higher excited state had a larger Rényi entropy, larger Tsallis entropy, and smaller Onicescu information energy. However, this trend was not definite and the singlet–triplet reversal occurred for Rényi entropy, Tsallis entropy and Onicescu information energy at a certain range of order α .

Plasmon spectrum of graphene monolayer on substrate

2019 ◽  
Vol 33 (09) ◽  
pp. 1950102
Author(s):  
I. N. Askerzade ◽  
R. T. Askerbeyli
Keyword(s):  
Substrate Material ◽  
Plasmon Mode ◽  
Monolayer Graphene ◽  
Graphene Monolayer ◽  
Multilayer Graphene ◽  
Linear Dispersion ◽  
Long Wavelength ◽  
Theoretical Considerations ◽  
Plasmon Spectrum ◽  
Good Agreement

Plasmon modes in monolayer graphene on substrate are analyzed taking into account the thickness of graphene and substrate material layer in the evaluation of Coulomb potential. It is shown that plasmon mode in graphene monolayer has linear dispersion in contrast to multilayer graphene in long-wavelength limit. The slope of plasmon spectrum is determined by the thickness and dielectric constant of substrate. Obtained results are in good agreement with experimental data and other theoretical considerations.

Sign in / Sign up

Export Citation Format

Share Document