Theoretical characterization and many-body expansion analysis of BF

Shalabi, A.S.; Kamel, Karim; Assem, M.M.

doi:10.1007/s002140050088

Cited by 3 publications

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“…The vibrational frequencies we have calculated are in excellent agreement with those reported previously from computations and from Raman or infrared spectroscopy. For example, Ystenes et al have calculated the frequencies of AlCl 3 using a number of basis sets. 22a,e Their “recommended values” (the experimental ones) 27 of 151, 214, 375, and 616 cm -1 compare favorably with our frequencies of 140, 192, 378, and 613 cm -1 calculated at the MP2/6-311+G(d,p) level with a 0.95 scaling factor. Another recent theoretical assessment of the frequencies finds values of 154, 213, 402, and 642 cm -1 22f.…”

Section: Resultsmentioning

confidence: 49%

“…For example, Ystenes et al have calculated the frequencies of AlCl 3 using a number of basis sets. 22a,e Their “recommended values” (the experimental ones) 27 of 151, 214, 375, and 616 cm -1 compare favorably with our frequencies of 140, 192, 378, and 613 cm -1 calculated at the MP2/6-311+G(d,p) level with a 0.95 scaling factor. Another recent theoretical assessment of the frequencies finds values of 154, 213, 402, and 642 cm -1 22f. Our corresponding scaled MP2/6-311+G(d,p) frequencies for AlCl 4 - are 109, 171, 337, and 493 cm -1 as compared to the best computed values of 117, 179, 339, and 486 cm -1 22a and the experimental values of 119, 182, 346, and 488 cm -1 .…”

Section: Resultsmentioning

confidence: 49%

“…Figures −6 provide the structures and conformations of the species studied as determined from MP2/6-311+G(d,p) optimizations, except for ClHAl 2 Cl 7 - , where MP2/3-21+G(d,p) was the method used. Structures and energies for AlCl 3 ( C 3 v ), Al 2 Cl 6 ( D 2 d ), 22a-b AlCl 4 - ( T d ), 22a,b,d,23c, Al 2 Cl 7 - ( C 2 ), 22b,23c,24a-b,d,e, AlCl 2 + ( D ∞ h ), 22g,23c, and HAlCl 4 ( C s ) 22d have been reported recently from various calculations, and our results are essentially the same as the most reliable of these. The agreement with experimental data, where available, is exceptionally good in most cases (Table ).…”

Section: Resultsmentioning

confidence: 99%

“…Although the structures may be less reliable, Δ H f ° values, calculated using semiempirical methods, are in reasonable agreement with literature experimental values available for two molecules and three ions (Table ). In addition to the experimental data shown in Table , Petrie, using the G2 level of theory, has calculated the following enthalpies of formation at 0 K: 524 ± 20 kJ/mol for AlCl 2 + and −595 ± 20 kJ/mol for AlCl 3 22g…”

Section: Resultsmentioning

confidence: 99%

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Thermodynamic Calculations for Reactions Involving Hydrogen Halide Polymers, Ions, and Lewis Acid Adducts. 3. Systems Constituted from Al³⁺, H⁺, and Cl^-

1999

Inorg. Chem.

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Semiempirical (MNDO, AM1 and PM3), ab initio (HF/3-21+G(d,p), MP2/3-21+G(d,p), HF/6-311+G(d,p), and MP2/6-311+G(d,p)), and density functional (BVWN/3-21+G(d,p) and BVWN/6-311+G(d,p)) energy minimization and frequency calculations have been carried out on AlCl(3), AlCl(4)(-), AlCl(2)(+), HAlCl(4), HAlCl(3)(+), and ClHAlCl(4)(-). The same computational set, except for MP2/6-311+G(d,p) frequency calculations, was performed on Al(2)Cl(6) and Al(2)Cl(7)(-). For ClHAl(2)Cl(7)(-), only semiempirical calculations, as well as Hartree-Fock and BVWN optimizations using the 3-21+G(d,p) and 6-311+G(d,p) basis sets, were carried out along with Hartree-Fock frequency determinations. DeltaG degrees, DeltaH degrees, and DeltaS degrees values have been calculated for a number of reactions involving these species along with a variety of ions derived from HCl. Thermodynamic data and equilibrium constants at 298 K are presented for 22 reactions using calculations at the best level, along with a comparison of DeltaG degrees values obtained from all molecular orbital methods used.

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Section: Resultsmentioning

confidence: 49%

Section: Resultsmentioning

confidence: 49%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

Thermodynamic Calculations for Reactions Involving Hydrogen Halide Polymers, Ions, and Lewis Acid Adducts. 3. Systems Constituted from Al³⁺, H⁺, and Cl^-

1999

Inorg. Chem.

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“…The non-additivity nadd term [25,[56][57][58][59][60][61] is a measure of cooperative interactions among the subsystems Here …”

Section: Resultsmentioning

confidence: 99%

CO adsorption on Ni, Pd, Cu and Ag deposited on MgO, CaO, SrO and BaO: Density functional calculations

Halim

Assem

Shalabi

et al. 2009

Applied Surface Science

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Spin transition energies of Cr in complexes and CO binding with Cr deposited on S²⁻and Se²⁻anion impurities of MgO (001) surface density functional theory calculations

Shalabi¹,

Aal²,

Assem³

et al. 2012

Phys. Scr.

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An attempt has been made to analyze the spin transition energies of Cr, a representative example of transition metals, in a variety of complexes formed at regular (001) surfaces of MgO, as well as the adsorption of CO by means of hybrid density functional theory calculations and embedded cluster models. Clusters of moderate sizes are embedded in the simulated Coulomb fields that closely approximate the Madelung fields of the host surfaces. While the spin states of Cr are reduced and preserved in all complexes, be they defect-free or-defect containing, the combined effects of the adsorbate and the substrate in the defect-free OC.Cr.Mg9O13O2− complex were strong enough to favor the low-spin state and to quench the spin. The deposited Cr atoms enhance the adsorption of CO. The significant weakening of bond strength between OC and Cr in complexes supports the concept of bond order conservation. The natural bond orbital (NBO) analysis reveals that the electronic structure of the adsorbed metal represents a qualitative change with respect to that of the free metal. The effects of spin contamination on the geometry, Mulliken charges and adsorption energy are examined. The binding of CO precursor is dominated by the E (i)Cr.CO pairwise additive components, and the role of the support was not restricted to supporting the metal. Relations are established between the process of spin transition and the energy gaps between frontier orbitals. The results show that the spin state of adsorbed metal atoms on oxide supports and the role of precursor molecules in the properties of spin transition energies of Cr in complexes need to be explicitly taken into account.

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Theoretical characterization and many-body expansion analysis of BF

Cited by 3 publications

References 0 publications

Thermodynamic Calculations for Reactions Involving Hydrogen Halide Polymers, Ions, and Lewis Acid Adducts. 3. Systems Constituted from Al³⁺, H⁺, and Cl^-

Thermodynamic Calculations for Reactions Involving Hydrogen Halide Polymers, Ions, and Lewis Acid Adducts. 3. Systems Constituted from Al³⁺, H⁺, and Cl^-

CO adsorption on Ni, Pd, Cu and Ag deposited on MgO, CaO, SrO and BaO: Density functional calculations

Spin transition energies of Cr in complexes and CO binding with Cr deposited on S²⁻and Se²⁻anion impurities of MgO (001) surface density functional theory calculations

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Theoretical characterization and many-body expansion analysis of BF

Cited by 3 publications

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Thermodynamic Calculations for Reactions Involving Hydrogen Halide Polymers, Ions, and Lewis Acid Adducts. 3. Systems Constituted from Al3+, H+, and Cl-

Thermodynamic Calculations for Reactions Involving Hydrogen Halide Polymers, Ions, and Lewis Acid Adducts. 3. Systems Constituted from Al3+, H+, and Cl-

CO adsorption on Ni, Pd, Cu and Ag deposited on MgO, CaO, SrO and BaO: Density functional calculations

Spin transition energies of Cr in complexes and CO binding with Cr deposited on S2−and Se2−anion impurities of MgO (001) surface density functional theory calculations

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Thermodynamic Calculations for Reactions Involving Hydrogen Halide Polymers, Ions, and Lewis Acid Adducts. 3. Systems Constituted from Al³⁺, H⁺, and Cl^-

Thermodynamic Calculations for Reactions Involving Hydrogen Halide Polymers, Ions, and Lewis Acid Adducts. 3. Systems Constituted from Al³⁺, H⁺, and Cl^-

Spin transition energies of Cr in complexes and CO binding with Cr deposited on S²⁻and Se²⁻anion impurities of MgO (001) surface density functional theory calculations