Electronic structure calculations of rare-earth intermetallic compound YAg using ab initio methods

A rare-earth-containing compound, ytterbium aluminium antimonide, Yb3AlSb3 (Ca3AlAs3-type structure), has been successfully synthesized within the Yb–Al–Sb system through flux methods. According to the Zintl formalism, this structure is nominally made up of (Yb2+)3[(Al1−)(1b – Sb2−)2(2b – Sb1−)], where 1b and 2b indicate 1-bonded and 2-bonded, respectively, and Al is treated as part of the covalent anionic network. The crystal structure features infinite corner-sharing AlSb4 tetrahedra, [AlSb2Sb2/2]6−, with Yb2+ cations residing between the tetrahedra to provide charge balance. Herein, the synthetic conditions, the crystal structure determined from single-crystal X-ray diffraction data, and electronic structure calculations are reported.

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Ab Initio Electronic Structure Calculations by Auxiliary-Field Quantum Monte Carlo

Handbook of Materials Modeling ◽

10.1007/978-3-319-44677-6_47 ◽

2020 ◽

pp. 123-149

Author(s):

Shiwei Zhang

Keyword(s):

Monte Carlo ◽

Electronic Structure ◽

Ab Initio ◽

Quantum Monte Carlo ◽

Electronic Structure Calculations ◽

Auxiliary Field ◽

Structure Calculations ◽

Ab Initio Electronic Structure

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Electronic Structure Calculations on a Real-Space Mesh with Multigrid Acceleration

MRS Proceedings ◽

10.1557/proc-408-145 ◽

1995 ◽

Vol 408 ◽

Author(s):

D. J. Sullivan ◽

E. L. Briggs ◽

C. J. Brabec ◽

J. Bernholc

Keyword(s):

Electronic Structure ◽

Ab Initio ◽

Large Scale ◽

Electronic Structure Calculations ◽

High Energy ◽

Real Space ◽

Parallel Architectures ◽

Wurtzite Phase ◽

Ongoing Work ◽

Structure Calculations

AbstractWe have developed a set of techniques for performing large scale ab initio calculations using multigrid accelerations and a real-space grid as a basis. The multigrid methods permit efficient calculations on ill-conditioned systems with long length scales or high energy cutoffs. We discuss the design of pseudopotentials for real-space grids, and the computation of ionic forces. The technique has been applied to several systems, including an isolated C60 molecule, the wurtzite phase of GaN, a 64-atom cell of GaN with the Ga d-states in valence, and a 443-atom protein. The method has been implemented on both vector and parallel architectures. We also discuss ongoing work on O(N) implementations and solvated biomolecules.

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Grid Enabled High Level ab initio Electronic Structure Calculations for the N2+N2 Exchange Reaction

Computational Science and Its Applications – ICCSA 2012 - Lecture Notes in Computer Science ◽

10.1007/978-3-642-31125-3_29 ◽

2012 ◽

pp. 371-386 ◽

Cited By ~ 2

Author(s):

Marco Verdicchio ◽

Leonardo Pacifici ◽

Antonio Laganà

Keyword(s):

Electronic Structure ◽

Ab Initio ◽

Exchange Reaction ◽

Electronic Structure Calculations ◽

High Level ◽

Structure Calculations ◽

Ab Initio Electronic Structure

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Summary, Conclusions, and Future Trends

Neural Networks in Chemical Reaction Dynamics ◽

10.1093/oso/9780199765652.003.0015 ◽

2012 ◽

Author(s):

Lionel Raff ◽

Ranga Komanduri ◽

Martin Hagan ◽

Satish Bukkapatnam

Keyword(s):

Electronic Structure ◽

Complex Systems ◽

Human Brain ◽

Ab Initio ◽

Large Scale ◽

Dimensional Space ◽

Electronic Structure Calculations ◽

Potential Surfaces ◽

The 1960S ◽

Structure Calculations

Since the introduction of classical and semiclassical molecular dynamics (MD) methods in the 1960s and Gaussian procedures to conduct electronic structure calculations in the 1970s, a principal objective of theoretical chemistry has been to combine the two methods so that MD and quantum mechanical studies can be conducted on ab initio potential surfaces. Although numerous procedures have been attempted, the goal of first principles, ab initio dynamics calculations has proven to be elusive when the system contains five or more atoms moving in unrestricted three-dimensional space. For many years, the conventional wisdom has been that ab initio MD calculations for complex systems containing five or more atoms with several open reaction channels are presently beyond our computational capabilities. The rationale for this view are (a) the inherent difficulty of high level ab initio quantum calculations on complex systems that may take numerous, large-scale computations impossible, (b) the large dimensionality of the configuration space for such systems that makes it necessary to examine prohibitively large numbers of nuclear configurations, and (c) the extreme difficulty associated with obtaining sufficiently converged results to permit accurate interpolation of numerical data obtained from electronic structure calculations when the dimensionality of the system is nine or greater. Neural networks (NN) derive their name from the fact that their interlocking structure superficially resembles the neural network of a human brain and from the fact that NNs can sense the underlying correlations that exist in a database and properly map them in a manner analogous to the way a human brain can execute pattern recognition. Artificial neurons were first proposed in 1943 by Warren McCulloch, a neurophysiologist, and Walter Pitts, an MIT logician. NNs have been employed by engineers for decades to assist in the solution of a multitude of problems. Nevertheless, the power of NNs to assist in the solution of numerous problems that occur in chemical reaction dynamics is just now being realized by the chemistry community.

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The 3s versus 3p Rydberg state photodissociation dynamics of the ethyl radical

Physical Chemistry Chemical Physics ◽

10.1039/c9cp04273c ◽

2019 ◽

Vol 21 (41) ◽

pp. 23017-23025 ◽

Cited By ~ 1

Author(s):

Sonia Marggi Poullain ◽

David V. Chicharro ◽

Alexandre Zanchet ◽

Luis Rubio-Lago ◽

Alberto García-Vela ◽

...

Keyword(s):

Electronic Structure ◽

Ab Initio ◽

Rydberg State ◽

Rydberg States ◽

Electronic Structure Calculations ◽

Velocity Map Imaging ◽

Ethyl Radical ◽

Structure Calculations

Photodissociation dynamics of the ethyl radical from the 3s vs. 3p Rydberg states studied by velocity map imaging and ab initio electronic structure calculations.

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Mechanisms of photoreactivity in hydrogen-bonded adenine–H2O complexes

Physical Chemistry Chemical Physics ◽

10.1039/c8cp05305g ◽

2019 ◽

Vol 21 (26) ◽

pp. 14238-14249 ◽

Cited By ~ 4

Author(s):

Xiuxiu Wu ◽

Johannes Ehrmaier ◽

Andrzej L. Sobolewski ◽

Tolga N. V. Karsili ◽

Wolfgang Domcke

Keyword(s):

Wave Function ◽

Electronic Structure ◽

Ab Initio ◽

Electronic Structure Calculations ◽

Water Molecules ◽

Photoinduced Reactions ◽

Structure Calculations ◽

Hydrogen Bonded

The mechanisms of photoinduced reactions of adenine with water molecules in hydrogen-bonded adenine–water complexes were investigated with ab initio wave-function-based electronic-structure calculations.

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