Hartree-Fock perturbed-cluster treatment of local defects in crystals

Pisani, Cesare; Corà, Furio; Nada, R.H.; Orlando, Roberto

doi:10.1016/0010-4655(94)90163-5

Cited by 70 publications

(36 citation statements)

References 31 publications

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“…In this case we find a higher defect formation energy for the F þ center than for the F center for the unrelaxed system. This result is in qualitative agreement with the calculated data of Scorza et al [36] who used the EMBED program [38,39] at the HF level in combination with second order Møller-Plesset theory for an estimate of the correlation energy.…”

Section: The Neutral and Charged Oxygen Vacancysupporting

confidence: 88%

First‐principles periodic and semiempirical cyclic cluster calculations for single oxygen vacancies in crystalline Al₂O₃

Janetzko

Ėvarestov

Bredow³

et al. 2004

Physica Status Solidi (b)

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Single neutral and positively charged oxygen vacancies (F and F þ centers) in a-Al 2 O 3 are investigated using the supercell model (SCM) at the Hartree-Fock (HF) and density functional theory (DFT) level and the cyclic cluster model (CCM) implemented in the semiempirical MSINDO method. Results of supercell and cyclic cluster calculations for the cohesive energy of the perfect Al 2 O 3 crystal are compared with the experimental value for the heat of atomization. The defect formation energy of the unrelaxed F center is calculated with the SCM. The CCM is used to calculate the defect formation energy of the F and the F þ centers. Relaxation effects for the nearest neighbors (NN) and the nextnearest neighbors (NNN) of the F and F þ centers are investigated. The obtained values are compared to other theoretical literature data.

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Section: The Neutral and Charged Oxygen Vacancysupporting

confidence: 88%

First‐principles periodic and semiempirical cyclic cluster calculations for single oxygen vacancies in crystalline Al₂O₃

Janetzko

Ėvarestov

Bredow³

et al. 2004

Physica Status Solidi (b)

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“…[12,13,14,15,16,17,18]). Several types of embedded cluster techniques have been used successfully to study the structure and properties of defects in ionic oxides, such as MgO (see, for example, [19,20,21,22,23,24]), CaO [25] and SiO 2 [26,27].…”

Section: Introductionmentioning

confidence: 99%

Structure and spectroscopic properties of oxygen divacancy in yttrium-stabilized zirconia

Ramo

Shluger

2008

J. Phys.: Conf. Ser.

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Abstract. We have studied the structure and spectroscopic properties of the oxygen divacancy defect in Yttrium-stabilized ZrO2 using periodic and embedded cluster methods and GGA and B3LYP density functionals. The results demonstrate that the defect spectroscopic properties depend on the particular arrangement of Y dopants near vacancies. The optical transition energies calculated for the negatively charged state of the divacancy at 2.8 eV and 3.3 eV are in agreement with experimental data. The second set of transitions between 1.9 eV and 2.7 eV corresponds to the electron transfer between vacancies. The calculated EPR g-tensor values are in agreement with other works. The results support the proposed attribution of the optical absorption peaking at 3.3 eV and related EPR spectra to Zr 3+ ions in the YSZ matrix, however, they are not fully conclusive due to dependence on Y concentration.

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“…Of course, approximations to the form of the functional are admissible and often necessary. However, additional approximations, which are introduced in many embedding schemes [10][11][12][13][19][20][21]24 during the SCF procedure for determining the ground-state density matrix, may bare a high risk of seriously violating the variational principle. 9…”

Section: Dϭ͕d͉dsdϭdٙtr͑sd͒ϭn͖ ͑3͒mentioning

confidence: 99%

A strictly variational procedure for cluster embedding based on the extended subspace approach

Gutdeutsch

Birkenheuer

Rösch

1998

The Journal of Chemical Physics

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Even if an isolated defect results only in a local perturbation of the electron density, the wave function and the first-order reduced density matrix may still exhibit a long-range response to the defect. We present an axiomatic approach to the construction of a general-purpose embedding scheme which is able to cope with this problem. We start from a list of requirements, which we consider pertinent to an accurate embedding technique, and we proceed to demonstrate that the extended subspace approach recently proposed by Head and Silva [J. Chem. Phys. 104, 3244 (1996)] is the minimal realization of such an embedding scheme. The variational principle, strict fulfillment of the Pauli exclusion principle, a finite dimensional parameter space, and the possibility to perform the minimization by a standard SCF (self-consistent field) procedure are the key requirements which lead to a constrained SCF procedure. Self-embedding consistency and local completeness of the Hilbert space can then be realized by a mathematically very simple construction principle for the active subspace which can be formulated independent of any basis set. We analyze the spatial structure of the resulting minimal orbital space by means of tight-binding model Hamiltonians. For metal systems, we find active and frozen constrained SCF spaces to necessarily interlock in a strong and complicated fashion.

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Hartree-Fock perturbed-cluster treatment of local defects in crystals

Cited by 70 publications

References 31 publications

First‐principles periodic and semiempirical cyclic cluster calculations for single oxygen vacancies in crystalline Al₂O₃

First‐principles periodic and semiempirical cyclic cluster calculations for single oxygen vacancies in crystalline Al₂O₃

Structure and spectroscopic properties of oxygen divacancy in yttrium-stabilized zirconia

A strictly variational procedure for cluster embedding based on the extended subspace approach

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Hartree-Fock perturbed-cluster treatment of local defects in crystals

Cited by 70 publications

References 31 publications

First‐principles periodic and semiempirical cyclic cluster calculations for single oxygen vacancies in crystalline Al2O3

First‐principles periodic and semiempirical cyclic cluster calculations for single oxygen vacancies in crystalline Al2O3

Structure and spectroscopic properties of oxygen divacancy in yttrium-stabilized zirconia

A strictly variational procedure for cluster embedding based on the extended subspace approach

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Product

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First‐principles periodic and semiempirical cyclic cluster calculations for single oxygen vacancies in crystalline Al₂O₃

First‐principles periodic and semiempirical cyclic cluster calculations for single oxygen vacancies in crystalline Al₂O₃