The influence of the optical pulse shape on excited state dynamics in provitamin D3

Tang, Kuo Chun; Sension, Roseanne J.

doi:10.1039/c1fd00035g

Cited by 9 publications

(26 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The biexponential nature of the ESA decay can be explained within the context of two different models -sequential internal conversion between two distinct excited states, or rapid branching along two distinct pathways followed by parallel decay of these two populations. The parallel model seems more consistent with the experimental data, 5,99 and is supported by a recent computational study on Pro. 6,37 Furche and coworkers performed NAMD simulations of Pro along with the CHD simulations discussed above.…”

Section: Excited State Properties Of Provitamin Dsupporting

confidence: 81%

Ultrafast polyene dynamics: the ring opening of 1,3-cyclohexadiene derivatives

Arruda

Sension

2014

Phys. Chem. Chem. Phys.

Self Cite

View full text Add to dashboard Cite

The light activated ring-opening reaction of the 1,3-cyclohexadiene chromophore finds application in optical control, optical switching, optical memory, light activated molecular machines, photobiology, photochromic materials, and conformation-specific photocatalysts. The development of ultrafast spectroscopic methods and powerful computational methods have accelerated the understanding and facilitated the application of this important chromophore in a wide range of systems. Here we look at the current state of theoretical and experimental understanding for the ring-opening reaction of the isolated cyclohexadiene molecule and the ring-opening reactions of substituted cyclohexadienes, including fulgides, diarylethenes, and provitamin D.

show abstract

Section: Excited State Properties Of Provitamin Dsupporting

confidence: 81%

Ultrafast polyene dynamics: the ring opening of 1,3-cyclohexadiene derivatives

Arruda

Sension

2014

Phys. Chem. Chem. Phys.

Self Cite

View full text Add to dashboard Cite

show abstract

“…This previtamin D 3 triene structure then undergoes a [1,7] sigmatropic hydride shift to form cholecalciferol (vitamin D 3 ) . In contrast to the ring-opening photoreaction, which occurs on a time scale of picoseconds, − the thermal hydride shift occurs on the order of hours to days. − The photochemistry of vitamin D has received much experimental ,− ,− and theoretical ,− attention due to the fundamental biological importance of the reaction and even its potential use in photoactivated devices …”

Section: Introductionmentioning

confidence: 99%

Probing the Biexponential Dynamics of Ring-Opening in 7-Dehydrocholesterol

2016

Self Cite

View full text Add to dashboard Cite

Our prior discovery of a novel biexponential photochemical ring-opening in 7-dehydrocholesterol (DHC) to previtamin D3 [ Tang J. Chem. Phys. 2011 , 134 , 104503 ] is further explored with ultrafast transient absorption spectroscopy, and the results are compared with recently reported high-level theoretical calculations. Three types of experiments are reported. First, variation of the excitation wavelength from 297 to 266 nm leaves the excited state dynamics unaffected. The biexponential decay of the excited state absorption is independent of excitation wavelength with time constants of 0.57 ± 0.06 and 1.88 ± 0.09 ps, in excellent agreement with the results reported earlier (0.56 ± 0.06 and 1.81 ± 0.15 ps) following excitation at 266 nm. Second, variation of the chirp of the excitation pulse influences the relative amplitude of the fast and slow decay components but has no influence on the photoproduct yield. Third, a 545 nm pulse delayed by 0.64 ps with respect to the initial 266 nm pulse was used to perturb the "slow" population and probe the influence of additional electronic or vibrational energy on the reaction process. The results show ultrafast internal conversion Sn → S1 on a ca. 150 fs time scale but no subsequent effect on the reaction dynamics. The experiments reported here are consistent with the recent state averaged complete active space self-consistent field ab initio multiple spawning (SA-CASSCF-AIMS) calculations of Snyder et al. [ J. Phys. Chem. Lett. 2016 , 7 , 2444 ] that assign the biexponential decay to nonequilibrium dynamics related to the opening and closing motion of the cyclohexadiene ring moiety on the excited state surface. These new experiments support the model prediction that the biexponential dynamics does not involve multiple minima and demonstrate the direction for new experimental designs to manipulate the product yields and pathways.

show abstract

“…In particular, Sension and co-workers have conducted rigorous studies on CHD and a number of its derivatives in solution (e.g., alphaphellandrene, a-TP) [126,128,134,135]. This group has also shown that the basic physics translates to larger systems with cyclic diene moieties such as provitamin D [135][136][137]. Fig.…”

Section: Probing Ultrafast Excited State Dynamics In Ring Opening Sysmentioning

confidence: 95%

Uncovering molecular relaxation processes with nonlinear spectroscopies in the deep UV

et al. 2013

View full text Add to dashboard Cite

a b s t r a c tNonlinear laser spectroscopies in the deep UV spectral range are motivated by studies of biological systems and elementary processes in small molecules. This perspective article discusses recent technical advances in this area with a particular emphasis on diffractive optic based approaches to four-wave mixing spectroscopies. Applications to two classes of systems illustrate present experimental capabilities. First, experiments on DNA components at cryogenic temperatures are used to uncover features of excited state potential energy surfaces and vibrational cooling mechanisms. Second, sub-200 fs internal conversion processes and coherent wavepacket motions are investigated in cyclohexadiene and a-terpinene.Finally, we propose new experimental directions that combine methods for producing few-cycle UV laser pulses in noble gases with incoherent detection methods (e.g., photoionization) in experiments with time resolution near a singlefemtosecond. These measurements are motivated by knowledge of extremely fast non-adiabatic dynamics and the resolution of electronic wavepacket motions in molecules.

show abstract

The influence of the optical pulse shape on excited state dynamics in provitamin D3

Cited by 9 publications

References 37 publications

Ultrafast polyene dynamics: the ring opening of 1,3-cyclohexadiene derivatives

Ultrafast polyene dynamics: the ring opening of 1,3-cyclohexadiene derivatives

Probing the Biexponential Dynamics of Ring-Opening in 7-Dehydrocholesterol

Uncovering molecular relaxation processes with nonlinear spectroscopies in the deep UV

Contact Info

Product

Resources

About