Enthalpies of formation of homoleptic dimethylamido compounds of tantlum (V), molybdenum (III), molybdenum (IV), tungsten (III) and tungsten (VI). Enthalpy contributions of metal–metal triple bonds

Adedeji, Festus A.; Cavell, Kingsley J.; Cavell, S.; Connor, Joseph A.; Pilcher, G.; Skinner, H. A.; Zafarani-Moattar, Mohamed T.

doi:10.1039/f19797500603

Cited by 15 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…From these results, we have calculated an average PDMAT vaporization enthalpy value of 97.5 ± 27 kJ mol −1 at 31 °C. This result is in the range of the literature values for the total pressure 26–28. Using the second law of thermodynamics, PDMAT average partial enthalpies of sublimation for the two species Ta[N(CH 3 ) 2 ] 4 and Ta[N(CH 3 ) 2 ] 5 are 63 ± 8 kJ mol −1 and 45 ± 10 kJ mol −1 , respectively.…”

Section: Pdmat Thermodynamic Behaviorsupporting

confidence: 72%

Developments of TaN ALD Process for 3D Conformal Coatings

Brizé

Prieur

Violet

et al. 2011

Chemical Vapor Deposition

View full text Add to dashboard Cite

International audienceThere is a growing interest in producing tantalum nitride (TaN) thin films for various industrial applications. For example, in microelectronics, the development of IC technology is driven by the need to increase both performance and functionality while reducing power and cost. This goal can be achieved by several solutions among which the introduction of architecture enhancements such as 3D integration. The most challenging step is the deposition of a conformal, continuous, and adherent diffusion barrier. In this work, atomic layer deposition (ALD) of TaN thin films is explored using the combination between the thermodynamical behavior of the precursor, mass transfer in the reactor, and the operating conditions. TaN thin film deposition on very complex shape substrates, such as nanodots, TSV, silicon nanowires, and carbon nanotubes, has been evaluated

show abstract

Section: Pdmat Thermodynamic Behaviorsupporting

confidence: 72%

Developments of TaN ALD Process for 3D Conformal Coatings

Brizé

Prieur

Violet

et al. 2011

Chemical Vapor Deposition

View full text Add to dashboard Cite

show abstract

“…The essential diffi culties are clearly evident, in a representative way, for the M 2 (NMe 2 ) 6 molecules. 96 102 The latter is so weak that this may well be tantamount to an estimate of the Cr-Cr bond energy. The dissociation energy of the Rh−Rh bond 103 in Rh 2 (OEP) 2 has been shown to be 69 ± 3 kJ mol -1 .…”

Section: Bond Energiesmentioning

confidence: 98%

Physical, Spectroscopic and Theoretical Results

Cotton

2005

Multiple Bonds Between Metal Atoms

View full text Add to dashboard Cite

Structural Correlations Bond orders and bond lengthsThroughout the preceding chapters of this book we have reported and in some cases discussed the lengths of the multiple bonds between metal atoms. We have reported in tabular form most of the M-M distances that have been determined crystallographically. It is now time to make some general comments on these distances in relation to our understanding of the M-M bonds.It is a general qualitative rule in chemistry that bond lengths and bond orders are inversely related. In some limited areas, particularly with the fi rst-row elements carbon, nitrogen, and oxygen, quantitative relationships expressing bond length as a single-valued function of bond order are well known. However, these quantitative relationships are based heavily on faith, as well as fact. Bond lengths are facts; bond orders are not. In the process of inferring a bond order from a bond length one is often getting out no more than what was put in to begin with.We shall not further digress into a discussion of the philosophical ambiguities of these quantitative bond order-bond length correlations because they have proven to be useful, within their own sphere of application. However, there is no a priori reason to expect that similar procedures will (or will not!) work in the very different realm of metal-to-metal bonds. Experience is the only test, and experience thus far has shown that M-M bonds cannot usefully be treated in such a way.In the realm of M-M bonds it is best to invoke only a qualitative inverse relationship between bond order and bond length and to defi ne bond order only in a qualitative or ordinal way. In this book we have used the term M-M bond order only to indicate how many electron pairs are believed, on the basis of essentially qualitative considerations, to play a signifi cant part in holding the pair of metal atoms together. We condemn as foolish and hopeless any effort to associate a unique, precise, quantitative bond order with each and every M-M internuclear distance.In principle, M-M bond lengths, like others, should be amenable to treatment by the method of molecular mechanics, and some efforts [1][2][3][4] (hampered by a dearth of necessary experimental data) to do this have been reported. In general the results are encouraging and can account for

show abstract

“…In the formation of 2 and 3 from thermolysis of 1 , a Ta–NMe 2 bond and a N–SiMe 3 bond are cleaved, and the π bond in TaNSiMe 3 and the Si–N bond in 2 are formed (Scheme ). Bond energies in 1 and 4 are unknown . Breaking of the Si–N bond in 1 is probably compensated for by the Si–N bond formed in 2 .…”

mentioning

confidence: 99%

Formation of the Imide [Ta(NMe₂)₃(μ-NSiMe₃)]₂ through an Unprecedented α-SiMe₃ Abstraction by an Amide Ligand

et al. 2011

View full text Add to dashboard Cite

Ta(NMe(2))(4)[N(SiMe(3))(2)] (1) undergoes the elimination of Me(3)Si-NMe(2) (2), converting the -N(SiMe(3))(2) ligand to the ═NSiMe(3) ligand, to give the imide "Ta(NMe(2))(3)(═NSiMe(3))" (3) observed as its dimer 4. CyN═C═NCy captures 3 to yield guanidinates Ta(NMe(2))(3-n)(═NSiMe(3))[CyNC(NMe(2))NCy](n) [n = 1 (5), 2 (6)]. The kinetic study of α-SiMe(3) abstraction in 1 gives ΔH(‡) = 21.3(1.0) kcal/mol and ΔS(‡) = -17(2) eu.

show abstract

Enthalpies of formation of homoleptic dimethylamido compounds of tantlum (V), molybdenum (III), molybdenum (IV), tungsten (III) and tungsten (VI). Enthalpy contributions of metal–metal triple bonds

Abstract: Solution, combustion and other calorimetric studies on dimethylamido-metal compounds of Ta, Mo, and W have led to the following enthalpies of formation at 25°C (kJ mol-') : * (IBP) isothermal bomb process.

Cited by 15 publications

References 0 publications

Developments of TaN ALD Process for 3D Conformal Coatings

Developments of TaN ALD Process for 3D Conformal Coatings

Physical, Spectroscopic and Theoretical Results

Formation of the Imide [Ta(NMe₂)₃(μ-NSiMe₃)]₂ through an Unprecedented α-SiMe₃ Abstraction by an Amide Ligand

Contact Info

Product

Resources

About

Enthalpies of formation of homoleptic dimethylamido compounds of tantlum (V), molybdenum (III), molybdenum (IV), tungsten (III) and tungsten (VI). Enthalpy contributions of metal–metal triple bonds

Abstract: Solution, combustion and other calorimetric studies on dimethylamido-metal compounds of Ta, Mo, and W have led to the following enthalpies of formation at 25°C (kJ mol-') : * (IBP) isothermal bomb process.

Cited by 15 publications

References 0 publications

Developments of TaN ALD Process for 3D Conformal Coatings

Developments of TaN ALD Process for 3D Conformal Coatings

Physical, Spectroscopic and Theoretical Results

Formation of the Imide [Ta(NMe2)3(μ-NSiMe3)]2 through an Unprecedented α-SiMe3 Abstraction by an Amide Ligand

Contact Info

Product

Resources

About

Formation of the Imide [Ta(NMe₂)₃(μ-NSiMe₃)]₂ through an Unprecedented α-SiMe₃ Abstraction by an Amide Ligand