Conformational control over an aldehyde fragment by selective vibrational excitation of interchangeable remote antennas

We apply vibrational antennas (OH or NH2 group) to achieve unprecedented conformational control over the heavy aldehyde fragment in 2-formyl-2H-azirine, using selective vibrational excitations of the OH or NH2 stretching overtones and combination modes.

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Low lying oscillations of deformed nuclei

EPJ Web of Conferences ◽

10.1051/epjconf/201817802009 ◽

2018 ◽

Vol 178 ◽

pp. 02009

Author(s):

Ani Aprahamian ◽

Shelly R. Lesher

Keyword(s):

Nuclear Structure ◽

Vibrational Excitation ◽

Deformed Nuclei ◽

Vibrational Excitations

Low-lying oscillations of the intrinsic deformed shape of a nucleus remain an open challenge in nuclear structure. The question or challenge revolves around the viability of single or multiple quanta of vibrational excitations superimposed on the equilibrium, deformed shape of a nucleus. The K=2 or “γ” vibrations are fairly widespread and nominally conform to expectations whereas the existence of the K=0 or “β” vibrational excitation is yet to be distinguished from other possible origins including the coexistence of other potential minima.

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Selective conformational control by excitation of NH imino vibrational antennas

Physical Chemistry Chemical Physics ◽

10.1039/c9cp05370k ◽

2019 ◽

Vol 21 (45) ◽

pp. 24935-24949 ◽

Cited By ~ 3

Author(s):

Sándor Góbi ◽

Igor Reva ◽

István Pál Csonka ◽

Cláudio M. Nunes ◽

György Tarczay ◽

...

Keyword(s):

Experimental Evidence ◽

Vibrational Excitation ◽

Imino Group ◽

Conformational Control ◽

Sh Group

We provide experimental evidence for the occurrence of selective and reversible conformational control over the SH group by vibrational excitation of remote NH groups. Using an imino group that acts as a molecular antenna has no precedents.

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EFFECTS OF ROTATIONAL AND VIBRATIONAL EXCITATION ON THE STEREODYNAMICS OF THE O (D-1) + HCl → OH + Cl REACTION

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633609005386 ◽

2009 ◽

Vol 08 (06) ◽

pp. 1177-1184 ◽

Cited By ~ 15

Author(s):

QIANG WEI ◽

VICTOR WEI-KEH WU ◽

BO ZHOU

Keyword(s):

Cross Sections ◽

Collision Energy ◽

Energy Surface ◽

Vibrational Excitation ◽

Classical Trajectory ◽

Rotational Excitation ◽

Title Reaction ◽

Vibrational Excitations ◽

Product Vector ◽

Good Agreement

The stereodynamics of the title reaction on the ground 1 1A′ potential energy surface (PES) has been studied using quasi-classical trajectory (QCT) method. Collision energy of 6.4 kcal/mol is considered, and vector properties including angular momentum alignment distributions and polarization-dependent differential cross-sections (PDDCS) of the product OH are presented. Furthermore, the influence of reagent rotational excitation and vibrational excitation on the product vector properties has also been studied in the present work. The results indicate that the distribution of the P(θr) and P(ϕr) are sensitively affected by the rotational and vibrational excitation. The rotational excitation decreases the degree of alignment and orientation, while vibrational excitation increases the degree of alignment and orientation. The PDDCS (2π/σ)(dσ20/dωt) and (2π/σ)(dσ22+/dωt) are sensitively influenced by rotational and vibrational excitations, while the PDDCS ((2π/σ)(dσ00/dωt)) and (2π/σ)(dσ21-/dωt) are not. The preference of forward scattering has been found from the results of PDDCS ((2π/σ)(dσ00/dωt)), which is in good agreement with the experimental results.

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Influence of Laser Vibrational Excitations of Ethylene Molecules in Laser-Assisted Combustion Diamond Synthesis

MRS Proceedings ◽

10.1557/opl.2015.6 ◽

2015 ◽

Vol 1734 ◽

Author(s):

L.S. Fan ◽

Y.S. Zhou ◽

M.X. Wang ◽

Y. Gao ◽

L. Liu ◽

...

Keyword(s):

Vibrational Excitation ◽

Flame Temperature ◽

Combustion Process ◽

Energy Coupling ◽

Deposition Process ◽

Resonance Excitation ◽

Diamond Deposition ◽

Coupling Energy ◽

Vibrational Excitations ◽

Coupling Path

ABSTRACTLaser-induced vibrational excitation of ethylene molecules was integrated to the CVD diamond deposition process for an in-depth understanding of the energy coupling path in chemical reactions and an alternative method to enhance the diamond deposition. On- and off-resonance excitations of ethylene molecules were achieved via tuning the incident laser wavelengths centered at 10.532 µm. With the same amount of laser power absorbed, the chemical reaction is highly accelerated with on-resonance vibrational excitation whereas energy coupling with off-resonance excitations was less efficient in influencing the combustion process. The diamond deposition rate was enhanced by a factor of 5.7 accompanied with an improvement of diamond quality index with the on-resonance excitation at 10.532 μm. The measured flame temperature demonstrated that the resonant vibrational excitation was an efficient route for coupling energy into the reactant molecules and steering the combustion process.

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THEORETICAL STUDIES OF STEREODYNAMICS FOR THE H+ + H2 (ν = 0–3, j = 0) → H2 + H+ REACTION

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633609004654 ◽

2009 ◽

Vol 08 (03) ◽

pp. 403-415 ◽

Cited By ~ 19

Author(s):

CUIHUA ZHANG ◽

WENQIN ZHANG ◽

MAODU CHEN

Keyword(s):

Angular Momentum ◽

Ground State ◽

Collision Energy ◽

Vibrational Excitation ◽

Ground Surface ◽

Title Reaction ◽

Vector Correlations ◽

Vibrational Excitations ◽

Trajectory Method ◽

Rotational Angular Momentum

The stereodynamics calculation was carried out for the title reaction by quasiclassical trajectory method on the ground surface of KBNN potential energy surface. The vector correlations are determined at initial ground state and vibrational excitation of the reagent H 2. The results show that the rotational polarization is affected lightly by collision energy and strongly by reagent excitation for title reaction. The rotational alignments are almost isotropic at several collision energies on initial ground state of the reagent H 2, which means that the product rotational angular momentum is weakly polarized (or no polarized). Nevertheless, the polarization of product rotational angular momentum is enhanced remarkably at the vibrational excitations of the reagent H 2 in collision energy of 0.524 eV.

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Strong-field-induced wave packet dynamics in carbon dioxide molecule

Faraday Discussions ◽

10.1039/c6fd00152a ◽

2016 ◽

Vol 194 ◽

pp. 463-478 ◽

Cited By ~ 10

Author(s):

Artem Rudenko ◽

Varun Makhija ◽

Aram Vajdi ◽

Thorsten Ergler ◽

Markus Schürholz ◽

...

Keyword(s):

Carbon Dioxide ◽

Wave Packet ◽

Strong Field ◽

Vibrational Excitation ◽

Chem Phys ◽

Final State ◽

Vibrational Dynamics ◽

Carbon Dioxide Molecule ◽

Vibrational Excitations ◽

Ionic States

Temporal evolution of electronic and nuclear wave packets created in strong-field excitation of the carbon dioxide molecule is studied employing momentum-resolved ion spectroscopy and channel-selective Fourier analysis. Combining the data obtained with two different pump-probe set-ups, we observed signatures of vibrational dynamics in both, ionic and neutral states of the molecule. We consider far-off-resonance two-photon Raman scattering to be the most likely mechanism of vibrational excitation in the electronic ground state of the neutral CO2. Using the measured phase relation between the time-dependent yields of different fragmentation channels, which is consistent with the proposed mechanism, we suggest an intuitive picture of the underlying vibrational dynamics. For ionic states, we found signatures of both, electronic and vibrational excitations, which involve the ground and the first excited electronic states, depending on the particular final state of the fragmentation. While our results for ionic states are consistent with the recent observations by Erattupuzha et al. [J. Chem. Phys.144, 024306 (2016)], the neutral state contribution was not observed there, which we attribute to a larger bandwidth of the 8 fs pulses we used for this experiment. In a complementary measurement employing longer, 35 fs pulses in a 30 ps delay range, we study the influence of rotational excitation on our observables, and demonstrate how the coherent electronic wave packet created in the ground electronic state of the ion completely decays within 10 ps due to the coupling to rotational motion.

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