Hartree-Fock Ab Initio Treatment of Crystalline Systems

Pisani, Cesare; Dovesi, Roberto; Roetti, C.

doi:10.1007/978-3-642-93385-1

Cited by 745 publications

(637 citation statements)

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“…The Coulomb and exchange series are summed directly and truncated using an overlap criterion with thresholds of 10 −7 , 10 −7 , 10 −7 , 10 −7 , and 10 −14 as described previously. 67,73 Reciprocal space sampling for the bulk structure was performed on a Pack-Monkhorst net with a shrinking factor IS = 8 along each periodic direction.…”

Section: Computational Detailsmentioning

confidence: 99%

Water adsorption on rutile TiO2(110) for applications in solar hydrogen production: A systematic hybrid-exchange density functional study

et al. 2012

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Periodic hybrid-exchange density functional theory calculations are used to predict the structure of water on the rutile TiO 2 (110) surface ( 1 ML), which is an important first step towards understanding the photocatalytic processes that occur in solar water splitting. A detailed model describing the water-water and water-surface interactions is developed by exploring thoroughly the adsorption energetics. The possible adsorption mode-molecular, dissociative, or mixed-and the binding energy are studied as a function of coverage and arrangement, thus separation, of adsorbed species. These dependencies (coverage and arrangement) have a significant influence on the nature of the interactions involved in the H 2 O-TiO 2 system. The importance of both direct intermolecular and surface-mediated interactions between surface species is emphasized. Finally, to gain insight into the photooxidation of adsorbed species at the surface, the electronic structure of the predicted adsorbate-substrate geometries is analyzed in terms of total and projected density of states.

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Section: Computational Detailsmentioning

confidence: 99%

Water adsorption on rutile TiO2(110) for applications in solar hydrogen production: A systematic hybrid-exchange density functional study

et al. 2012

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“…First, due to the smallness of the energy values considered, different technical parameters of the calculations [Hartree-Fock (HF) tolerances [32,33], fit domains [24], auxiliary basis sets [34], etc.] are responsible for a noise in the energies.…”

Section: Ups1mentioning

confidence: 99%

“…Although the calculated energies are numerically in quite good agreement with the experiment, our best theoretical Under such circumstances, it is important to estimate the sign and magnitude of the errors, remaining in the theoretical description. First, due to the smallness of the energy values considered, different technical parameters of the calculations [Hartree-Fock (HF) tolerances [32,33], fit domains [24], auxiliary basis sets [34], etc.] are responsible for a noise in the energies.…”

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confidence: 99%

Approaching an exact treatment of electronic correlations at solid surfaces: The binding energy of the lowest bound state of helium adsorbed on MgO(100)

et al. 2014

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In this work we employ ab initio electronic structure theory at a very high level to resolve a long standing experimental controversy; the interaction between helium and the MgO (100) surface has been studied extensively by other groups, employing diverse experimental approaches. Nevertheless, the binding energy of the lowest bound state is still unclear: the existence of a state at around −5.5 meV is well established but a state at −10 meV has also been reported. The MgO (100)-He system captures the fundamental physics involved in many adsorption problems; the weak binding is governed by long-range electronic correlation for which a fully predictive theory applicable to the solid state has been elusive. The above-mentioned experimental controversy can now be resolved on the basis of the calculations presented in this work. We performed three-dimensional vibrational dynamics calculations on a highly accurate potential-energy surface. The latter was constructed using a method which systematically approaches the exact limit in its treatment of electronic correlation. The outcome is clear: our calculations do not support the existence of a bound state around −10 meV. The interaction between molecules and crystalline surfaces is of great fundamental and technological interest and is extensively studied both experimentally and theoretically [1][2][3]. One particular example is physisorption and scattering of helium atoms on oxide surfaces. In the last two decades the latter process, employing molecular-beam techniques, has been developed into a powerful tool for the analysis of surface structure and dynamics [4][5][6][7][8]. It is particularly useful for studying insulating surfaces, such as MgO [4,9]. At close proximity the helium-surface interaction potential is dominated by the exponentially growing corrugated repulsive wall, which is a consequence of the mutual exchange repulsion between the helium and surface electron densities. The repulsive potential is two-dimensional (2D) corrugated and leads to a complicated diffraction pattern for helium scattered from the surface. In the range of intermediate He-surface distances, there exists a very shallow attractive potential due to the weak van der Waals interactions, which drops off with distance from the surface as 1/z 3 [10]. Such a potential can support several bound states (in fact several 2D bands of bound states), which correspond to vibrational levels of helium atoms physisorbed on the surface.The delicacy of the balance between different components of the helium-surface interaction makes quantitatively accurate theoretical predictions of the behavior of helium atoms on the surface extremely difficult. Standard density functional theory (DFT), which is the common tool in solid-state simulations (i.e., local-density approximation, generalized gradient approximation, or hybrids), does not capture van der Waals dispersion. In principle it can be used for calculating * r.martinezcasado@imperial.ac.uk † denis.usvyat@chemie.uni-regensburg.de the repulsive wall at th...

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“…It is calculated from the RHF wave function of the cluster and the crystal. The wave functions of the cluster and the crystal are calculated with the CRYSTAL program [15][16][17][18][19], using a minimal STO-3c basis set 1201. There is a correction for the boundary errors of all the atoms in the cluster except for the atoms of the HOSiA106 group and the correction potential is only added to the HOSiA1o6 group.…”

mentioning

confidence: 99%

“…If the overlaps between the involved AOS are below a threshold, the integral is approximated with multipolar expansions [15,19]. The thresholds were lop5 for Coulomb integrals and for exchange integrals.…”

mentioning

confidence: 99%

Large basis sets and geometry optimizations in embedded cluster calculations

Teunissen

Jansen

1995

Int J of Quantum Chemistry

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mIn the embedded cluster method, a cluster is embedded in a correction potential. This potential adds the long-range electrostatic forces of the crystal and subtracts the electrostatic potential of the boundary errors of the cluster. The correction potential is calculated from the wave function of the cluster and the crystal. So far, the method has only been used on a cluster having the same geometry and basis set as that of the crystal. Here, we calculated the adsorption energies of NH3 and NH: on an embedded zeolite cluster with different basis sets and modified geometries. We showed that a mixed basis set, a basis set having a large basis set on the atoms around the adsorption site and a minimal basis set on the atoms of the boundary of the cluster, yields adsorption energies close to that of the large basis set. The optimized geometries of the zeolite acidic site were almost equal for the nonembedded cluster, the embedded cluster, and the crystal. By combining the mixed basis set with a partial geometry optimization, an improved description of the adsorption process is obtained. 0 1995

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Hartree-Fock Ab Initio Treatment of Crystalline Systems

Cited by 745 publications

References 0 publications

Water adsorption on rutile TiO2(110) for applications in solar hydrogen production: A systematic hybrid-exchange density functional study

Water adsorption on rutile TiO2(110) for applications in solar hydrogen production: A systematic hybrid-exchange density functional study

Approaching an exact treatment of electronic correlations at solid surfaces: The binding energy of the lowest bound state of helium adsorbed on MgO(100)

Large basis sets and geometry optimizations in embedded cluster calculations

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