A DFT investigation on the electronic properties of octahaloditechnetate anions: Correlation between charge and bond strength

Pastor, Michael B.; Zhao, Qinxin

doi:10.1016/j.ica.2014.09.022

Cited by 4 publications

(2 citation statements)

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“…For comparison, both B3LYP and BH&HLYP functionals were used in calculations for all nine models. As shown in Tables and , computations using functional BH&HLYP provided optimized geometry more closely resembling the experimental data, which is in accord with recent observations from calculations carried out on octahaloditechnetate anions . Because of this, subsequent data analyses were done using computations with the BH&HLYP functional.…”

Section: Resultssupporting

confidence: 85%

Exploring the Intricacies of Weak Interactions in Metal–Metal Bonds Using an Unsymmetrical Carbonyl Precursor and a Triple-Bonded W₂⁶⁺ Paddlewheel

et al. 2016

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Stepwise reaction of W(CO)6 with tetramethylated bicyclic guanidinate ligands, characterized by a central C(N)3 unit joining two fused six-membered rings with CH2CMe2CH2 units spanning two of the nitrogen atoms, allowed isolation of W2(μ-CO)2(μ-TMhpp)2(η(2)-TMhpp)2, 1, a precursor of W2(TMhpp)4Cl2 ( J. Am. Chem. Soc. 2013 , 135 , 17889 ; TMhpp = [(CH2CMe2CH2)2(C(N)3)]). Subsequent heating of 1 followed by reaction with TlPF6 generates [W2(TMhpp)4](PF6)2, 2. Compound 1 has an edge-sharing bioctahedral (ESBO) arrangement with a W2(μ-CO)2(4+) core having semibridging carbonyl groups, while 2 has a paddlewheel structure with a W2(6+) core spanned by four tetramethyl-substituted bicyclic guanidinate ligands. This compound also has hexafluorophosphate anions along the metal-metal bond that are nestled within methylene groups with the aid of a network of weak C-H···F interactions that prevent a close approach of the fluorine atoms to the dimetal unit. Theoretical computations were carried out on ditungsten model complexes supported by three ligand sets: bicyclic guanidinate, guanidinate, and formamidinate. The computations show that the π-accepting ability of the carbonyl groups significantly lowers the energy of the σ* orbital, and thus, the energy falls below that of the δ orbital. This information along with the diamagnetism of both 1 and 2-as shown by the sharp signals in the (1)H NMR spectra that support a lack of unpaired electrons (S = 0)-is consistent with the electronic configuration of σ(2)π(2)σ*(2)δ(2) (π(2)δ(2)) and thus a formal bond order of 2 for 1 and σ(2)π(4) for the triple-bonded W2(6+) core in 2. A comparison of the W-W bond lengths in 2, its chloro precursor W2(TMhpp)4Cl2, and the corresponding analogue W2(hpp)4Cl2 shows a substantial effect from the axially coordinated ligand, distal lone pair in determining the length of the metal-metal bond for these paddlewheel species. The importance of the ligands in tuning the energy level of the metal-metal bonds that may lead to dramatic changes in physical properties is also discussed. It is noteworthy that bicyclic guanidinates with the strongest π-donating ability push upward the energy level of the δ orbital, thus allowing the compounds to be easily oxidized.

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Section: Resultssupporting

confidence: 85%

Exploring the Intricacies of Weak Interactions in Metal–Metal Bonds Using an Unsymmetrical Carbonyl Precursor and a Triple-Bonded W₂⁶⁺ Paddlewheel

et al. 2016

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“…25 Several recent papers have studied the different cases of dymolibdenum compounds with special ligands. [26][27][28][29][30][31][32][33][34][35] A complete revision of these is out of the scope of this study. Some of them use DFT as a tool for understanding the structure of these compounds [30][31][32][33][34][35] .…”

Section: Introductionmentioning

confidence: 99%

Electronic structure and spectroscopy of homoleptic compounds of dimolybdenum using TDDFT

Vilarrubias

2016

Can. J. Chem.

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Ten compounds of dimolybdenum are studied using Density Functional Theory (DFT) and Time-Dependent Density Functional Theory (TDDFT). The energy of the strongest symmetry-allowed bands is calculated. The results are then compared with experimental data, when available. The PW91 functional gives results for geometry and for the energy of the δ→δ* band which shows good agreement with experimental data. However, B3LYP functional gives more realistic values for the whole spectrum when the results are compared with experimental data. Finally, the different values of energy of these bands are explained analyzing the molecular orbitals involved in these transitions. Some ligands can act as an unsaturated system in conjugation with the delta bond, modifying the energies of the electronic transitions.

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Theoretical analysis of TcO3(OH), TcS3(OH) and TcSe3(OH)

Büyükmumcu

2016

J Radioanal Nucl Chem

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A DFT investigation on the electronic properties of octahaloditechnetate anions: Correlation between charge and bond strength

Cited by 4 publications

References 57 publications

Exploring the Intricacies of Weak Interactions in Metal–Metal Bonds Using an Unsymmetrical Carbonyl Precursor and a Triple-Bonded W₂⁶⁺ Paddlewheel

Exploring the Intricacies of Weak Interactions in Metal–Metal Bonds Using an Unsymmetrical Carbonyl Precursor and a Triple-Bonded W₂⁶⁺ Paddlewheel

Electronic structure and spectroscopy of homoleptic compounds of dimolybdenum using TDDFT

Theoretical analysis of TcO3(OH), TcS3(OH) and TcSe3(OH)

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A DFT investigation on the electronic properties of octahaloditechnetate anions: Correlation between charge and bond strength

Cited by 4 publications

References 57 publications

Exploring the Intricacies of Weak Interactions in Metal–Metal Bonds Using an Unsymmetrical Carbonyl Precursor and a Triple-Bonded W26+ Paddlewheel

Exploring the Intricacies of Weak Interactions in Metal–Metal Bonds Using an Unsymmetrical Carbonyl Precursor and a Triple-Bonded W26+ Paddlewheel

Electronic structure and spectroscopy of homoleptic compounds of dimolybdenum using TDDFT

Theoretical analysis of TcO3(OH), TcS3(OH) and TcSe3(OH)

Contact Info

Product

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Exploring the Intricacies of Weak Interactions in Metal–Metal Bonds Using an Unsymmetrical Carbonyl Precursor and a Triple-Bonded W₂⁶⁺ Paddlewheel

Exploring the Intricacies of Weak Interactions in Metal–Metal Bonds Using an Unsymmetrical Carbonyl Precursor and a Triple-Bonded W₂⁶⁺ Paddlewheel