A theoretical study of metal—ligand bond strengths (ML: L = OH, OCH3, SH, NH2, PH2, CH3, SiH3, CN and H) in the early transition metal systems Cl3ML (M = Ti, Zr and Hf) and late transition metal systems LCo(CO)4

doi:10.1016/S0277-5387(00)81788-X

Polyhedron

Volume 7, Issues 16–17, 1988, Pages 1625-1637

https://doi.org/10.1016/S0277-5387(00)81788-X Get rights and content

Abstract

The strength of metal—ligand bonds (ML: L = OH, OCH₃, SH, NH₂, PH₂, CN, CH₃, SiH₃ and H) in the early transition metal systems Cl₃ML (M = Ti, Zr and Hf) and late transition metal systems LCo(CO)₄ have been calculated by a non-local density functional method. For the early transition metal systems the TiL bond in Cl₃TiL was found to be quite polar, in particular for OCH₃, OH and NH₂. The order of the D(TiL) bond strength was calculated to be OH(453) > OCH₃(427) > CN(410) > NH₂(365) > SH(283) > CH₃(268) > H(251) > SiH ₃(211) > PH₂(191), where the numbers in parentheses are the bond energies in kJ mol⁻¹. The corresponding bond energies of the Cl₃ZrL systems were calculated to be between 25 kJ mol⁻¹ and 50 kJ mol⁻¹ higher. An additional increase in the ML bond energy of 10 kJ mol⁻¹ to 20 kJ mol⁻¹ was calculated in going from M = Zr to M = Hf. The ML bonds in the late transition metal systems LCo(CO)₄ were calculated to be weaker and less polar than the corresponding bonds in Cl₃TiL. The order for the bond strengths in LCo(CO)₄, was calculated to be CN(304) > OH(232) > H(230) > SiH₃(212) > SH(169) > CH₃ (160) > NH₂(146) > PH₂(145). The quite different order of stability for the ML bond strength in early and late transition metal systems was analysed in terms of electronic and steric factors.

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A theoretical study of metal—ligand bond strengths (ML: L = OH, OCH3, SH, NH2, PH2, CH3, SiH3, CN and H) in the early transition metal systems Cl3ML (M = Ti, Zr and Hf) and late transition metal systems LCo(CO)4

Abstract

Adv. Quantum. Chem.

Struct. Bonding (Berlin)

Top. Curr. Chem.

Chem. Rev.

J. Am. Chem. Soc.

J. Am. Chem. Soc.

NATO ASI

NATO ASI

J. Chem. Phys.

Chem. Phys.

Theory. Chim. Acta.

J. Chem. Phys.

Polyhedron

J. Am. Chem. Soc.

J. Am. Chem. Soc.

J. Am. Chem. Soc.

J. Am. Chem. Soc.

A theoretical study of metal—ligand bond strengths (ML: L = OH, OCH₃, SH, NH₂, PH₂, CH₃, SiH₃, CN and H) in the early transition metal systems Cl₃ML (M = Ti, Zr and Hf) and late transition metal systems LCo(CO)₄