Periodic trends in gas phase MH and MC bond energies

doi:10.1016/S0277-5387(00)81783-0

Polyhedron

Volume 7, Issues 16–17, 1988, Pages 1573-1581

https://doi.org/10.1016/S0277-5387(00)81783-0 Get rights and content

Abstract

Thermochemistry of simple transition metal species as determined by guided ion beam mass spectrometry is reviewed. Compounds which are discussed include metal hydrides (both ionic and neutral), metal methyls (ionic and neutral), ionic metal methylidenes and metal methylidynes, and bis-methyl metal ions. The periodic trends in this thermochemistry are discussed with an eye on developing ways of applying the data to condensed phase species.

The measurement of gas phase BDEs of transition metal species is just emerging from its infancy. The technological and theoretical tools necessary to obtain both accurate and precise values using beam techniques have only recently been developed, as have competing methods (such as photodisso ciation²⁸ and proton affinity measurements^43,44). In combination with values from more established techniques (such as high temperature mass spectrometry⁴⁵ and spectroscopy), this gas phase thermochemistry provides a wealth of data which can be analysed for its periodic trends. As outlined above, these analyses can provide intrinsic bond energies for ionic and neutral metal hydrides (57–60 kcal mol⁻¹), ionic and neutral metal methyls [2–8 kcal mol⁻¹ higher than D⁰(MH⁺) for cationic species, and ∼ 2 kcal mol⁻¹ less than D₀ (MH) for neutral species], ionic metal methylidenes ( ∼ 94 kcal mol⁻¹) and ionic metal methylidynes (∼ 130 kcal mol⁻¹). Further, the periodic trends can help to identify influential factors in determining the strength or weakness of a bond. These include electronic (essentially hybridization) and polarization effects. Continued studies on even more complex transition metal species should enable even closer relationships between gas and condensed phase thermochemistry to be forged.

References (46)

K.M. Ervin et al.
J. Chem. Phys.
(1985)
N. Aristov et al.
J. Am. Chem. Soc.
(1986)
R. Georgiadis et al.
J. Am. Chem. Soc.
(1986)
K.M. Ervin et al.
J. Chem. Phys.
(1986)
V.L. Talrose et al.
K.M. Ervin et al.
J. Chem. Phys.
(1987)
M.E. Weber et al.
J. Chem. Phys.
(1986)
J.L. Elkind et al.
J. Phys. Chem.
(1984)
B.H. Boo et al.
J. Am. Chem. Soc.
(1987)
J.B. Schilling et al.
J. Am. Chem. Soc.
(1986)

M.A. Vincent et al.

J. Phys. Chem.

(1982)

A.E. Alvarado-Swaisgood et al.

J. Phys. Chem.

(1985)

A.E. Alvarado-Swaisgood et al.

J. Phys. Chem.

(1985)

A.K. Rappe et al.

J. Chem. Phys.

(1986)

11.eM. Dupuis, B. L. Hammond and W. A. Lester, private...

L.G.M. Pettersson et al.

J. Chem. Phys.

(1987)

J.L. Elkind et al.

J. Phys. Chem.

(1985)

J.L. Elkind et al.

J. Chem. Phys.

(1986)

J.L. Elkind et al.

J. Am. Chem. Soc.

(1986)

J.L. Elkind et al.

J. Phys. Chem.

(1986)

J.L. Elkind et al.

J. Phys. Chem.

(1986)

J.L. Elkind et al.

J. Chem. Phys.

(1987)

J.L. Elkind et al.

J. Phys. Chem.

(1987)

J. L. Elkind, P. B. Armentrout, Int. J. Mass, Spect. Ion Proc., in...

P.B. Armentrout et al.

J. Am. Chem. Soc.

(1981)

L.F. Halle et al.

Organometallics

(1982)

R.H. Schultz et al.

J. Am. Chem. Soc.

(1988)

P.B. Armentrout et al.

J. Chem. Phys.

(1981)

Cited by (117)

Transition metal hydrides MH+/0/− (M = Sc−Zn): Benchmark study and periodic trends
2018, Computational and Theoretical Chemistry
Citation Excerpt :
In the past studies, we obtained some data, such as the bond energies (theoretical and experimental values), bond lengths and spectral properties of a large number of [M–H]+, as well as the excitation energy of TMHs [17–20]. Armentrout proved that the first and second rows of periodic trends of TMH are linear regression [21]. It provides a very valuable theoretical basis for this research.
Transition metal hydride (TMH) plays a critical role in the field of chemical catalysis and catalytic transformations. Knowledge of enthalpies for cleaving metal hydride bonds enables the prediction of chemical reactivity, such as for the bond-forming and bond breaking events that occur in a catalytic reaction especially in the hydrogenation of carbon dioxide. Thermochemistry of the first row TMHs, MH^+/0/− (M = Sc−Zn) were calculated at both the Density Functional Theory (DFT) level and the CCSD(T) level. Thermochemistry hydricity is the energy required to cleave an M–H bond to generate a hydride ion (H⁻). The heterolytic bond cleavage with proton dissociation is the acidity of the metal hydride. The homolytic bond-dissociation energy (BDE), involves formation H. Periodic trends of H⁻, H⁺, H donor ability are discussed and compared among the different elements and every MH^+/0/− systems. Note that, we can find suitable methods and avoid bad methods for different element. The study could give certain theoretical guidance on the catalysis of TMH.
Gas-phase ion chemistry of rare earths and actinides
2014, Handbook on the Physics and Chemistry of Rare Earths
Citation Excerpt :
Sc, Y, La, and Lu are the rare earths that have been examined by Armentrout and coworkers, and Table 8 presents a selection of bond dissociation energies of the monopositive cations. Periodic trends in the bond energies for the transition metals were uncovered and assessed in terms of the atomic electronic configurations and PEs, and this was an early seminal contribution of Armentrout and Beauchamp (Armentrout, 1990, 2003; Armentrout and Beauchamp, 1989; Armentrout and Clemmer, 1992; Armentrout and Georgiadis, 1988; Armentrout and Kickel, 1996; Armentrout et al., 1981, 1989; Kretzschmar et al., 2001). Some of these trends/correlations are illustrated by the examples presented in Figs. 22 and 23: in the former, the first-row (including Sc+) and the second-row (including Y+) transition metal ion hydride bond energies are plotted as a function of the atomic metal ion PE to an s1dn spin-decoupled state; in the latter, the bond energies of Sc+ to isoelectronic series of ligands, CH3, NH2, and OH or CH2, NH, and O, are plotted as a function of the number of electron lone pairs on the ligands or the presumed bond order.
Gas-phase chemistry studies of atomic and molecular rare earth and actinide ions have a well-founded history of more than three decades. In the gas phase, physical and chemical properties of elementary species can be studied in the absence of external perturbations. Due to the relative simplicity of gas-phase systems, compared to condensed-phase systems, solution or solid, it is possible to probe in detail the relationships between electronic structure, reactivity, and energetics, and the information obtained can be compared directly with results from theoretical models. Most of this research involves the use of a variety of mass spectrometry techniques, which provide the capacity to exert precise control over reactants and products. Many new rare earth and actinide molecular and cluster species have been identified that have expanded knowledge of the basic chemistry of these elements and provided links to condensed-phase processes. Several key thermodynamic values have been obtained for numerous elementary molecules. Such fundamental physicochemical studies have provided opportunities for the refinement and validation of computational methods as applied to the particularly challenging 4f lanthanides and 5f actinides. Among other applications, the roles of ligands, solvent molecules, and counterions have been examined at a molecular level. A deeper understanding of plasma chemistry, flame chemistry, radiolysis, and interstellar chemistry has relied on these types of studies. Important applications in analytical and biomedical mass spectrometry have also benefited from discoveries in this area.
Guided ion beam studies of transition metal-ligand thermochemistry
2003, International Journal of Mass Spectrometry
Studies of organometallic chemistry in the gas phase can provide substantial quantitative information regarding the interactions of transition metals with a wide variety of covalently and noncovalently bound ligands. In this review, the technique of guided ion beam tandem mass spectrometry for the measurement of thermodynamic information is highlighted. Periodic trends in covalent bonds between first, second, and a few third row transition metals and small ligands are discussed. Periodic trends in covalent versus noncovalent metal ligand bonds are compared and fluctuations in sequential noncovalent bonds (solvation) as a function of different metals are reviewed. In all cases, electronic effects that can be used to understand the various trends are elucidated. Finally, recent results for ligands covalently bound to metal clusters are reviewed.
Activation of CH<inf>4</inf>, C<inf>2</inf>H<inf>6</inf>, and C<inf>3</inf>H<inf>8</inf> by gas-phase Nb+ and the thermochemistry of Nb-ligand complexes
2000, International Journal of Mass Spectrometry
Citation Excerpt :
Nevertheless, the data in the methane systems leaves no doubt that the Nb+–CH2 BDE cannot be this low. There are no barriers to these reactions in excess of the endothermicity (which would raise the BDE anyway), as demonstrated by the efficiency of the reverse process [14,34]. The good agreement with the value obtained in the propane system where formation of NbCH2+ occurs by a different mechanism indicates that there are no obvious systematic effects in the determination of this BDE.
The kinetic energy dependence of the reactions of Nb⁺ (⁵D) with methane, ethane, and propane have been studied using guided ion beam mass spectrometry. It is found that dehydrogenation is efficient and the dominant process at low energies in all three reaction systems. At high energies, products resulting from both C–H and C–C cleavage processes are appreciable. The observation of dihydride and hydrido-methyl niobium cation products provides insight into the reaction mechanisms operating in these processes. The results for Nb⁺ are compared with those for the first-row transition metal congener V⁺ and the differences in behavior and mechanism discussed. Modeling of the endothermic reaction cross sections yields the 0 K bond dissociation energies (in electron volts) of D₀(Nb–H) > 2.3 ± 0.1, D₀(Nb⁺–2H) = 4.64 ± 0.06, D₀(Nb⁺–C) = 5.28 ± 0.15, D₀(Nb⁺–CH) = 6.02 ± 0.20, D₀(Nb⁺–CH₂) = 4.44 ± 0.09, D₀(Nb⁺–CH₃) = 2.06 ± 0.11, D₀[Nb⁺–(H)(CH₃)] = 4.78 ± 0.11, D₀(Nb⁺–C₂H) = 4.34 ± 0.19, D₀(Nb⁺–C₂H₂) = 2.90 ± 0.06, D₀(Nb⁺–C₂H₃) = 3.43 ± 0.21, D₀(Nb⁺–C₂H₄) = 2.8 ± 0.3, D₀(Nb⁺–C₂H₅) = 2.45 ± 0.12, D₀(Nb⁺–C₃H₂) = 5.25 ± 0.19, and lower limits for D₀(Nb⁺–C₃H₃) ≥ 3.76 ± 0.23 and D₀(Nb⁺–C₃H₅) ≥ 1.4 ± 0.1. The observation of exothermic processes sets lower limits for the bond energies of Nb⁺ to propyne and propene of 2.84 and 1.22 eV, respectively.
Activation of C<inf>2</inf>H<inf>6</inf>, C<inf>3</inf>H<inf>8</inf>, HC(CH<inf>3</inf>)<inf>3</inf>, and c-C<inf>3</inf>H<inf>6</inf> by gas-phase Ru+ and the thermochemistry of Ru-ligand complexes
1999, Journal of the American Society for Mass Spectrometry
The reactions of Ru⁺ with C₂H₆, C₃H₈, HC(CH₃)₃, and c-C₃H₆ at hyperthermal energies have been studied using guided ion beam mass spectrometry. It is found that dehydrogenation is efficient and the dominant process at low energies in all four reaction systems. At high energies, C–H cleavage processes dominate the product spectrum for the reactions of Ru⁺ with ethane, propane, and isobutane. C–C bond cleavage is a dominant process in the cyclopropane system. The reactions of Ru⁺ are compared with those of the first-row transition metal congener Fe⁺ and the differences in behavior and mechanism are discussed in some detail. Modeling of the endothermic reaction cross sections yields the 0-K bond dissociation energies (in eV) of D₀(Ru–H) = 2.27 ± 0.15, D₀(Ru⁺–C) = 4.70 ± 0.11, D₀(Ru⁺–CH) = 5.20 ± 0.12, D₀(Ru⁺–CH₂) = 3.57 ± 0.05, D₀(Ru⁺–CH₃) = 1.66 ± 0.06, D₀(Ru–CH₃) = 1.68 ± 0.12, D₀(Ru⁺–C₂H₂) = 1.98 ± 0.18, D₀(Ru⁺–C₂H₃) = 3.03 ± 0.07, and D₀(Ru⁺–C₃H₄) = 2.24 ± 0.12. Speculative bond energies for Ru⁺ = CCH₂ of 3.39 ± 0.19 eV and Ru⁺ = CHCH₃ of 3.19 ± 0.15 eV are also obtained. The observation of exothermic processes sets lower limits for the bond energies of Ru⁺ to ethene, propene, and isobutene of 1.34, 1.22, and 1.14 eV, respectively.
Gas-phase reactions of Tc+, Re+, Mo+ and Cu+ with alkenes
1998, Journal of Organometallic Chemistry
Organometallic complex ions, denoted as M⁺–L, where M=Tc, Re, Mo or Cu and L=C_cH_h, were produced by reacting laser-ablated M⁺ with alkenes (R=ethene, C₂H₄; propene, C₃H₆; cis-2-butene, C₄H₈; cyclohexene, C₆H₁₀ and 1,5-cyclooctadiene, C₈H₁₂). The compositions and abundances of the M⁺–L were determined by time-of-flight mass spectrometry. A primary goal was to elucidate gas-phase organotechnetium chemistry and differentiate the behaviors of Re⁺ and Mo⁺from that of Tc⁺. The ion pairs, Tc⁺+Re⁺and Tc⁺+Mo⁺, were coablated to provide direct comparisons of reactivities; these M⁺ were ablated from solid MO_x in a copper matrix, which generated Cu⁺, whose reactivity was also evaluated. For Tc⁺, Re⁺ and Mo⁺, H₂-loss from the alkene was the primary reaction channel, and the M⁺–L yields and extent of multiple H₂-loss (i.e. the reactivity) generally paralleled the size of R. Primary products were: M⁺C₂H₂ [R=C₂H₄]; M⁺C₃H₄ [R=C₃H₆]; M⁺C₄H₆ and M⁺C₄H₄ [R=C₄H₈]; M⁺C₆H₆ and M⁺{C₆H₆}₂ [R=C₆H₁₀] and M⁺C₈H₈ and M⁺C₈H₆ [R=C₈H₁₂]. For cycloalkenes, CC bond cleavage also occurred, e.g. M⁺+C₈H₁₂→M⁺C₆H₆+C₂H₆. The reactivity of Re⁺ was moderately greater than that of Tc⁺; thus for R=C₆H₁₀, the yield of Tc⁺C₆H₆ and Re⁺C₆H₆ were comparable but Tc⁺C₆H₄ was minor relative to Re⁺C₆H₄. Less coherent distinctions were observed between Tc⁺ and Mo⁺, although Tc⁺ was apparently slightly more reactive. Where ablated Mo⁺ were adequately abundant to measure Mo⁺L products, a greater reactivity, compared with naked M⁺, was indicated; for R=C₆H₁₀ the product yields were: Tc⁺C₆H₆/Tc⁺≈5% and TcO⁺C₆H₆/TcO⁺≈40%. The especially facile reaction, Tc₂⁺+C₄H₈→Tc₂⁺C₄H_h+[(8−h)/2]H₂ (h=6 or 4), indicated greater reactivity for Tc₂⁺ compared with Tc⁺. ‘Closed-shell’ (d¹⁰s⁰) Cu⁺ was relatively inert, generally producing primarily the adduct, Cu⁺R (condensation was insignificant for other M⁺). However, Cu⁺ distinctively produced abundant Cu⁺C₄H₆ (butadiene) from C₆H₁₀ and C₈H₁₂. The observed gas-phase organometallic chemistries of Cu⁺ and Mo⁺ are consistent with previous results by other techniques and with other organic substrates, and the reactivities of Tc⁺ and Re⁺ are in accord with general predictions.

View all citing articles on Scopus

View full text

Article preview

Polyhedron

Abstract

References (46)

J. Chem. Phys.

J. Am. Chem. Soc.

J. Am. Chem. Soc.

J. Chem. Phys.

J. Chem. Phys.

J. Chem. Phys.

J. Phys. Chem.

J. Am. Chem. Soc.

J. Am. Chem. Soc.

J. Phys. Chem.

J. Phys. Chem.

J. Phys. Chem.

J. Chem. Phys.

J. Chem. Phys.

J. Phys. Chem.

J. Chem. Phys.

J. Am. Chem. Soc.

J. Phys. Chem.

J. Phys. Chem.

J. Chem. Phys.

J. Phys. Chem.

J. Am. Chem. Soc.

Organometallics

J. Am. Chem. Soc.

J. Chem. Phys.

Cited by (117)

Transition metal hydrides MH<sup>+/0/−</sup> (M = Sc−Zn): Benchmark study and periodic trends

Gas-phase ion chemistry of rare earths and actinides

Guided ion beam studies of transition metal-ligand thermochemistry

Activation of CH<inf>4</inf>, C<inf>2</inf>H<inf>6</inf>, and C<inf>3</inf>H<inf>8</inf> by gas-phase Nb<sup>+</sup> and the thermochemistry of Nb-ligand complexes

Activation of C<inf>2</inf>H<inf>6</inf>, C<inf>3</inf>H<inf>8</inf>, HC(CH<inf>3</inf>)<inf>3</inf>, and c-C<inf>3</inf>H<inf>6</inf> by gas-phase Ru<sup>+</sup> and the thermochemistry of Ru-ligand complexes

Gas-phase reactions of Tc<sup>+</sup>, Re<sup>+</sup>, Mo<sup>+</sup> and Cu<sup>+</sup> with alkenes