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3 Quantum theory of atoms in molecules and the AIMAll software
2021Chemical bonding in the twenty-first century is inexorably linked to the application of quantum mechanics to chemistry. Today, the electronic structure of systems of moderate complexity can be reliably obtained even with desktop computers. The latter spit out intricate wavefunctions that need be analyzed if chemical insight, not only energies or energy
Ángel Martín Pendás, Carlo Gatti
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Performance of the Density Matrix Functional Theory in the Quantum Theory of Atoms in Molecules
The Journal of Physical Chemistry A, 2011The generalization to arbitrary molecular geometries of the energetic partitioning provided by the atomic virial theorem of the quantum theory of atoms in molecules (QTAIM) leads to an exact and chemically intuitive energy partitioning scheme, the interacting quantum atoms (IQA) approach, that depends on the availability of second-order reduced density
Marco, García-Revilla +3 more
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Journal of Chemical Theory and Computation, 2005
We make use of the Quantum Theory of Atoms in Molecules (QTAM) to partition the total energy of a many-electron system into intra- and interatomic terms, by explicitly computing both the one- and two-electron contributions. While the general scheme is formally equivalent to that by Bader et al., we focus on the separation and computation of the atomic ...
M A, Blanco +2 more
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We make use of the Quantum Theory of Atoms in Molecules (QTAM) to partition the total energy of a many-electron system into intra- and interatomic terms, by explicitly computing both the one- and two-electron contributions. While the general scheme is formally equivalent to that by Bader et al., we focus on the separation and computation of the atomic ...
M A, Blanco +2 more
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Quantum Theory of Atoms in Molecules: Results for the SR-ZORA Hamiltonian
The Journal of Physical Chemistry A, 2011The quantum theory of atoms in molecules (QTAIM) is generalized to include relativistic effects using the popular scalar-relativistic zeroth-order regular approximation (SR-ZORA). It is usually assumed that the definition of the atom as a volume bounded by a zero-flux surface of the electron density is closely linked to the form of the kinetic energy ...
James S M, Anderson, Paul W, Ayers
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Bonding in Endohedral Metallofullerenes as Studied by Quantum Theory of Atoms in Molecules
Chemistry – A European Journal, 2009AbstractMetal–cage and intracluster bonding was studied in detail by quantum theory of atoms in molecules (QTAIM) for the four major classes of endohedral metallofullerenes (EMFs), including monometallofullerenes Ca@C72, La@C72, M@C82 (M=Ca, Sc, Y, La), dimetallofullerenes Sc2@C76, Y2@C82, Y2@C79N, La2@C78, La2@C80, metal nitride clusterfullerenes Sc3N@
Alexey A, Popov, Lothar, Dunsch
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Revisiting the variational nature of the quantum theory of atoms in molecules
Chemical Physics Letters, 2006Abstract A simplified derivation of the variational nature of the real space basins used in the quantum theory of atoms in molecules (QTAM) is presented. We focus on pointing out the non-standard characteristics of the variational problem that is solved, and on clarifying some points that tend to be misinterpreted.
A. Martín Pendás +2 more
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International Journal of Quantum Chemistry, 2008
AbstractAtomic multipoles from the Quantum Theory of Atoms in Molecules (QTAIM), up to quadrupoles, and CHELPG charges are employed in the description of electrostatic properties of some small linear molecules: H2, HF, HCl, HBr, HCN, HNC, and CO. A proton is placed on the molecular axis in distances within the range 3–8 Å from the terminal atoms.
Eduardo F. F. Rodrigues +2 more
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AbstractAtomic multipoles from the Quantum Theory of Atoms in Molecules (QTAIM), up to quadrupoles, and CHELPG charges are employed in the description of electrostatic properties of some small linear molecules: H2, HF, HCl, HBr, HCN, HNC, and CO. A proton is placed on the molecular axis in distances within the range 3–8 Å from the terminal atoms.
Eduardo F. F. Rodrigues +2 more
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Two‐electron integrations in the Quantum Theory of Atoms in Molecules with correlated wave functions
Journal of Computational Chemistry, 2005AbstractA recent method proposed to compute two‐electron integrals over arbitrary regions of space [Martín Pendás, A. et al., J Chem Phys 2004, 120, 4581] is extended to deal with correlated wave functions. To that end, we use a monadic factorization of the second‐order reduced density matrix originally proposed by E. R.
Ángel Martín Pendás +2 more
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Quantum Theory of Atoms in Molecules–Dalton Revisited
1981Publisher Summary This chapter deals with the quantum mechanical definition of the average properties of an atom. It is demonstrated that the topological property that defines the atom determines the definition of its average properties. It reviews only the basic topological properties of a charge distribution in this chapter.
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Quantum-Mechanical Theory of Atoms in Molecules: A Relativistic Formulation
2001Analysis of chemical and physical phenomena often calls for partitioning of electronic properties into contributions from atoms, bonds, and molecular fragments [1]. Such a partitioning requires a theoretical prescription for discerning atoms in molecules (AIMs) that is not provided by the conventional formulation of quantum mechanics. However, AIMs can
Jerzy Cioslowski, Jacek Karwowski
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