Theoretical Study of the Binding of Silane (SiH4) with Borane (BH3), Diborane (B2H6), and Boron Trichloride (BCl3): The Role of Core–Electron Correlation

The role of valence and semi-core correlation in differentially stabilizing the intermediate spin-state of Fe(II)-porphyrins is analyzed. CASSCF treatment of the valence correlation, with a (32,34) active space containing metal 3d, 4d orbitals and the entire π system of the porphyrin, is necessary to stabilize the intermediate spin-state for this system. Semi-core correlation provides a quantitatively significant (~1.5 kcal/mol) but less important correction. Accounting for both types of correlation enlarges the (3Eg−5A1g) spin-gap to −5kcal/mol.

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On the Role of Valence and Semi-Core Electron Correlation on Spin-Gaps in Fe(II)-Porphyrins

10.26434/chemrxiv.7195370 ◽

2018 ◽

Author(s):

Giovanni Li Manni ◽

Daniel Kats ◽

David Tew ◽

Ali Alavi

Keyword(s):

Spin State ◽

Electron Correlation ◽

Core Electron ◽

Spin Gap ◽

Active Space ◽

Core Correlation ◽

Intermediate Spin ◽

Intermediate Spin State

The role of valence and semi-core correlation in differentially stabilizing the intermediate spin-state of Fe(II)-porphyrins is analyzed. CASSCF treatment of the valence correlation, with a (32,34) active space containing metal 3d, 4d orbitals and the entire π system of the porphyrin, is necessary to stabilize the intermediate spin-state for this system. Semi-core correlation provides a quantitatively significant (~1.5 kcal/mol) but less important correction. Accounting for both types of correlation enlarges the (3Eg−5A1g) spin-gap to −5kcal/mol.

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Theoretical study of oxygen atom transfer. The role of electron correlation

Journal of the American Chemical Society ◽

10.1021/ja00175a054 ◽

1990 ◽

Vol 112 (19) ◽

pp. 7065-7067 ◽

Cited By ~ 15

Author(s):

Robert D. Bach ◽

Joseph J. W. McDouall ◽

Amy L. Owensby ◽

H. Bernhard Schlegel

Keyword(s):

Oxygen Atom ◽

Electron Correlation ◽

Theoretical Study ◽

Atom Transfer ◽

Oxygen Atom Transfer

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Role of Man in Production and Social Systems Based on Digital Technologies

Sociology and Law ◽

10.35854/2219-6242-2020-1-6-13 ◽

2020 ◽

pp. 6-13

Author(s):

V. K. Potemkin

Keyword(s):

Theoretical Study ◽

Social Systems ◽

Digital Technologies ◽

Changing Role ◽

Consistent Approach ◽

Social Improvement

The article presents the results of a theoretical study of the influence processes of the developed digital technologies and the activities of enterprises and organizations on the changing role of man in labor and their social improvement. The necessity of a balanced and consistent approach to create conditions for the use of digital technologies in practical activities and determining the con- sequences not only in enterprises and organizations, but also in the conscious behavior and social realities of all workers, without exception, is substantiated. The main directions of the development of digital technologies are determined, involving the wide participation of workers in their use in enterprises and organizations.

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The Role of La2O3 in Enhancement the Radiation Shielding Efficiency of the Tellurite Glasses: Monte-Carlo Simulation and Theoretical Study

Materials ◽

10.3390/ma14143913 ◽

2021 ◽

Vol 14 (14) ◽

pp. 3913

Author(s):

Aljawhara H. Almuqrin ◽

Mohamed Hanfi ◽

K. G. Mahmoud ◽

M. I. Sayyed ◽

Hanan Al-Ghamdi ◽

...

Keyword(s):

Monte Carlo Simulation ◽

Theoretical Study ◽

Radiation Shielding ◽

Photon Flux ◽

Transmission Factor ◽

Tellurite Glasses ◽

Attenuation Coefficients ◽

Binary Glass ◽

Buildup Factors

The radiation shielding competence was examined for a binary glass system xLa2O3 + (1 − x) TeO2 where x = 5, 7, 10, 15, and 20 mol% using MCNP-5 code. The linear attenuation coefficients (LACs) of the glasses were evaluated, and it was found that LT20 glass has the greatest LAC, while LT5 had the least LAC. The transmission factor (TF) of the glasses was evaluated against thicknesses at various selected energies and was observed to greatly decrease with increasing thickness; for example, at 1.332 MeV, the TF of the LT5 glass decreased from 0.76 to 0.25 as the thickness increased from 1 to 5 cm. The equivalent atomic number (Zeq) of the glasses gradually increased with increasing photon energy above 0.1 MeV, with the maximum values observed at around 1 MeV. The buildup factors were determined to evaluate the accumulation of photon flux, and it was found that the maximum values for both can be seen at around 0.8 MeV. This research concluded that LT20 has the greatest potential in radiation shielding applications out of the investigated glasses due to the glass having the most desirable parameters.

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