The conformational stability of gaseous 1-butene studied by femtosecond nonlinear spectroscopy and ab initio calculations

Kunitski, Maksim; Knippenberg, Stefan; Dreuw, Andreas; Brutschy, Bernhard

doi:10.1016/j.vibspec.2010.07.006

Cited by 14 publications

(17 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…1-Butene possesses two conformers, cis and gauche, that exhibit similar energetics, but we consider only the gauche conformer according to IR strongfield results obtained for similar free-jet adiabatic expansion. 90 This system has the shallowest well and the most exoergic abstraction channel, in line with the slightly higher recoil of the FW scattered products. On the other hand, isobutene has both the deepest well for addition at the C1 site and the lowest exoergicity for HCl elimination; the scattering distribution is here more FW/BW symmetric and the average recoil slightly lowered.…”

Section: + Alkene Reactionsmentioning

confidence: 77%

Dynamics of Chlorine Atom Reactions with Hydrocarbons: Insights from Imaging the Radical Product in Crossed Beams

et al. 2014

View full text Add to dashboard Cite

We present a comprehensive overview of our ongoing studies applying dc slice imaging in crossed molecular beams to probe the dynamics of chlorine atom reactions with polyatomic hydrocarbons. Our approach consists in measuring the full velocity-flux contour maps of the radical products using vacuum ultraviolet "soft" photoionization at 157 nm. Our overall goal is to extend the range of chemical dynamics investigations from simple triatomic or tetraatomic molecules to systematic investigations of a sequence of isomers or a homologous series of reactants of intermediate size. These experimental investigations are augmented by high-level ab initio calculations which, taken together, reveal trends in product energy and angular momentum partitioning and offer deep insight into the reaction mechanisms as a function of structure, bonding patterns, and kinematics. We explore these issues in alkanes, for which only direct reactive encounters are found, and in unsaturated hydrocarbons, for which an addition-elimination mechanism competes with direct abstraction. The results for alkene addition-elimination in particular suggest a new view of these reactions: The only pathway to HCl elimination is accessed by means of roaming excursions of the Cl atom from the strongly bound adduct.

show abstract

Section: + Alkene Reactionsmentioning

confidence: 77%

Dynamics of Chlorine Atom Reactions with Hydrocarbons: Insights from Imaging the Radical Product in Crossed Beams

et al. 2014

View full text Add to dashboard Cite

show abstract

“…The sum over vibrations do not take into account the imaginary frequencies, thus lowering the ZPE for TSs, and in general the imaginary vibrations cannot be matched exactly to a given mode in the lower energy conformer. If such thing is possible, we can remove the same mode in the calculation of the stable conformer's ZPE and the corresponding ZPE of the TSs [26,27]. This could in principle be done for the T → S barrier where the imaginary frequency of the S conformer corresponds almost purely to the internal rotation of the phenyl planes, in a one-to-one correspondence with the lowest vibrational mode of the T conformer.…”

Section: Zero Point Vibrational Energiesmentioning

confidence: 99%

Towards the assignment of the REMPI spectrum of Ph₂O using CIS and TD-DFT methods

et al. 2013

View full text Add to dashboard Cite

Tentative assignment of the low-lying vibrational features of the first electronic excited singlet-state S 1 of diphenyl ether (Ph 2 O), obtained from resonance-enhanced multiphoton ionisation (REMPI) spectroscopy, is performed using CIS and timedependent density functional theory (TD-DFT) methods. The potential energy surfaces, regarding the rotation of the phenyl rings relatively to the C-O-C plane, are obtained at the B3LYP/6-31G(d) level of theory, for the ground-state of neutral and cationic Ph 2 O and for its first excited singlet state. The torsional barriers of the ground state of diphenyl ether were studied by means of quantum-chemical perturbations of increasing accuracy and an extrapolation to the complete basis set limit and full configuration interaction (FCI) was performed through the use of correlation consistent basis sets and the continued fraction method. The first adiabatic ionisation energy (AIE) of the twist conformer is computed at 8.60 eV in the FCI limit, much higher than the experimental results of Terlouw et al. (8.09 ± 0.03 eV) and Paiva et al. (7.8 ± 0.1 eV). The B3LYP result of 7.82 eV is, however, in reasonable agreement with the result of Paiva et al. The first singlet excitation energy for the twist conformation is found to be 5.5 eV at the CIS/6-311++G(d,p) level of theory. Some features of the experimental REMPI spectrum, previously obtained by one of the authors, are explained and a new insight on the ionisation energy of diphenyl ether is presented.

show abstract

“…Desde mediados del siglo XX, el gran desarrollo en el procesamiento del petróleo ha hecho hincapié en la necesidad de datos sobre el comportamiento de fases de los sistemas que contienen hidrocarburos tanto parafínicos, como olefínicos (Sage, 1948). Además, debido a la gran demanda mundial de los hidrocarburos, el conocimiento acabado de sus propiedades físicas y químicas fueron y siguen siendo de gran interés para la comunidad científica (Kunitski, et al 2011).…”

Section: Introductionunclassified

“…Wu et al (2008), aplicando espectroscopía de impulso de electrones, métodos ab initio y DFT al nivel B3LYP con la base aug-cc-pvtz, reportan que la forma gauge es la más estable, con una abundancia relativa del 69% frente al 31% de la conformación cis. Kunitski, et al (2011) realizaron su investigación mediante espectroscopía de mezcla de cuatro ondas degenerada de femtosegundo rotacional (fs DFWM) en condiciones de expansión supersónica. El espectro experimental fue reproducido exitosamente por una simulación ajustada utilizando una estructura única asignada al conformador gauche del 1-buteno.…”

Section: Introductionunclassified

Conformational study of 1-butene

et al. 2019

View full text Add to dashboard Cite

Se han investigado en forma teórica los rotámeros estables del 1-buteno, como así también la abundancia conformacional en su estado electrónico fundamental, en fase gaseosa y en condiciones normales de presión y temperatura. Se utilizó el método del funcional de la densidad (DFT), con los funcionales híbridos B3LYP, BHandHLYP y bases de Dunning aug-cc-PVnZ (n = D, T, Q), incorporados en el paquete profesional Gaussian 03. Se reportan tres confórmeros estables, dos de ellos isómeros ópticos con conformación no planar en la posición skew y una conformación plana en la posición cis. La abundancia relativa determinada para la conformación planar y no planar es de 70:30 aproximadamente.

show abstract

The conformational stability of gaseous 1-butene studied by femtosecond nonlinear spectroscopy and ab initio calculations

Cited by 14 publications

References 30 publications

Dynamics of Chlorine Atom Reactions with Hydrocarbons: Insights from Imaging the Radical Product in Crossed Beams

Dynamics of Chlorine Atom Reactions with Hydrocarbons: Insights from Imaging the Radical Product in Crossed Beams

Towards the assignment of the REMPI spectrum of Ph₂O using CIS and TD-DFT methods

Conformational study of 1-butene

Contact Info

Product

Resources

About

The conformational stability of gaseous 1-butene studied by femtosecond nonlinear spectroscopy and ab initio calculations

Cited by 14 publications

References 30 publications

Dynamics of Chlorine Atom Reactions with Hydrocarbons: Insights from Imaging the Radical Product in Crossed Beams

Dynamics of Chlorine Atom Reactions with Hydrocarbons: Insights from Imaging the Radical Product in Crossed Beams

Towards the assignment of the REMPI spectrum of Ph2O using CIS and TD-DFT methods

Conformational study of 1-butene

Contact Info

Product

Resources

About

Towards the assignment of the REMPI spectrum of Ph₂O using CIS and TD-DFT methods