Valence transitions in 1,3-cyclopentadiene, 1,3-cyclohexadiene, and 1,3-cycloheptadiene

McDiarmid, Ruth; Sabljić, Aleksandar; Doering, J. P.

doi:10.1063/1.449304

Cited by 54 publications

(56 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…54,57 Despite the inability to directly locate this dark state in absorption spectroscopy, several time-resolved studies have invoked non-adiabatic transitions involving it to explain the sub 200 fs dynamics observed in ion-and photoelectron signals subsequent to excitation to the bright (p,p * )-state. 23,58,59 The short timescales involved can also be inferred from the lack of detectable fluorescence of CPD, 60 further hinting at the involvement of a doubly excited state.…”

Section: Introductionmentioning

confidence: 99%

“…Numerous experimental studies have investigated the low-lying valence states in CPD [52][53][54][55][56][57] but only few have discussed the spectral position of the doubly excited state. 54,57 Despite the inability to directly locate this dark state in absorption spectroscopy, several time-resolved studies have invoked non-adiabatic transitions involving it to explain the sub 200 fs dynamics observed in ion-and photoelectron signals subsequent to excitation to the bright (p,p * )-state.…”

Section: Introductionmentioning

confidence: 99%

“…Furthermore, a totally symmetric, doubly excited configuration is possible, which will mix with V 2 , lowering the energy of this state and giving it partial doubly excited character. 54 This doubly excited configuration can be understood as arising from excitation of both of the ethylene units to their lowest triplet states but coupled to an overall singlet. 83 In the following we will use N, V 1 , and V 2 as diabatic labels associated with the electronic character of the state as described here, whereas S 0 -S 2 will be strictly adiabatic labels (i.e.…”

mentioning

confidence: 99%

“…Similarly, we find the vertical excitation energy to S 2 at this geometry to be 6.51 eV falling in between previous calculated values of 6.31-7.05 eV 85,86,[88][89][90] and slightly above the value of 6.2 eV suggested on the basis of experimental results. 54 The S 2 state possesses a large doubly excited character of $50% primarily due to the HOMO ! LUMO double (p) 2 !…”

mentioning

confidence: 99%

See 3 more Smart Citations

Between ethylene and polyenes - the non-adiabatic dynamics of cis-dienes

et al. 2012

View full text Add to dashboard Cite

Perturbation theory (MS-MR-CASPT2) treatment of the electronic structure, we have simulated the non-adiabatic excited state dynamics of cyclopentadiene (CPD) and 1,2,3,4-tetramethyl-cyclopentadiene (Me 4 -CPD) following excitation to S 1 . It is observed that torsion around the carbon-carbon double bonds is essential in reaching a conical intersection seam connecting S 1 and S 0 . We identify two timescales; the induction time from excitation to the onset of population transfer back to S 0 (CPD: $25 fs, Me 4 -CPD: $71 fs) and the half-life of the subsequent population transfer (CPD: $28 fs, Me 4 -CPD: $48 fs). The longer timescales for Me 4 -CPD are a kinematic consequence of the inertia of the substituents impeding the essential out-of-plane motion that leads to the conical intersection seam. A bifurcation is observed on S 1 leading to population transfer being attributable, in a 5 : 2 ratio for CPD and 7 : 2 ratio for Me 4 -CPD, to two closely related conical intersections. Calculated time-resolved photoelectron spectra are in excellent agreement with experimental spectra validating the simulation results.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Between ethylene and polyenes - the non-adiabatic dynamics of cis-dienes

et al. 2012

View full text Add to dashboard Cite

show abstract

“…The absorption spectrum of CHD can be found in [31][32][33], and there is a strong absorption band at 7.94 eV. The question then is whether absorption to such a high excited neutral state can lead to autoionization.…”

Section: Discussionmentioning

confidence: 99%

Vibrationally assisted below-threshold ionization

et al. 2017

View full text Add to dashboard Cite

We perform time-resolved UV pump (4.77 eV) and VUV probe (7.94 eV) measurements of internal conversion of 1,3-cyclohexadiene (CHD). Our measurements reveal a substantial ionization of the "hot" ground state following internal conversion despite the fact that our probe photon energy is below the ionization potential (8.21 eV). With the aid of electronic structure calculations, we interpret our results in terms of vibrationally assisted below threshold ionization, where vibrational energy is converted to electronic energy. The effect relies on both having vibrational modes which allow for this vibrational-electronic coupling, and exciting these modes during the internal conversion. We contrast our measurements in CHD with another similar molecule, cis,cis-1,3-cyclooctadiene (cis,cis-COD), for which we don't see the effect.

show abstract

The lower valence states of linear polyenes: Locations and identifications

Diarmid

1986

Int J of Quantum Chemistry

View full text Add to dashboard Cite

The experimental transition energy to the valence A, state of butadiene is used to validate a subset of the theoretical calculations that have been carried out on this molecule. The validated calculated A, transition energies of these calculations are then compared with the experimental B, transition energies to determine the relative state ordering in isolated, unsubstituted butadiene, hexatriene, and octatetraene. The A, origins are concluded to lie below the B , origins for all polyenes except butadiene. Experimental confirmation of this conclusion is presented. The extreme breadth of the A, transition, 1 .O eV, is noted. Some possible implications of this breadth are discussed.In this note, all currently available compatable experimental and theoretical information concerning the locations of the lower valence excited states of isolated, unsubstituted, short polyenes are compared, and an assignment is deduced that is consistent with this information and with the accepted major features of condensed phase and substituted polyene spectroscopy [ 11. Several predictions based on this analysis are presented.The experimental transition energies of two valence transitions each are now known for the all trans isomers of butadiene [2,3], hexatriene [4,5], and octatetraene [6,7] in the vapor phase. These are presented as solid symbols in Figure 1. The locations of the lower set of experimental transitions have long been known. They arise from allowed transitions to the B, state in each molecule [ 111. The B, transition energies indicated on the figure are origins. For use in our later analysis, this set is extrapolated to the decapentaene. The locations of the upper set of transitions have been determined by electron impact spectroscopy [ 3,5,7]. From experimental considerations, the upper set of transitions is assigned as arising from forbidden valence transitions. It is assumed, but not proven, that these are transitions to A, states. The transition energies indicated are vertical transitions.The first question that must be answered is whether or not the upper A, state observed in each molecule is the same. The answer is "no" for three reasons. The first is based on a comparison of the singlet A, and B, energy levels. The A,-B, energy gaps observed here in the triene and tetraene, 2.0 and 1.5 eV, respectively, are reasonable extrapolations of those observed in longer polyenes [ 121. The two transitions observed in each of these molecules thus correspond to the traditional B, and "cis" bands. The A,-B, gap observed in the diene, 1.6 eV, is significantly smaller than is 0 1986 John Wiley & Sons, Inc.

show abstract

Valence transitions in 1,3-cyclopentadiene, 1,3-cyclohexadiene, and 1,3-cycloheptadiene

Cited by 54 publications

References 20 publications

Between ethylene and polyenes - the non-adiabatic dynamics of cis-dienes

Between ethylene and polyenes - the non-adiabatic dynamics of cis-dienes

Vibrationally assisted below-threshold ionization

The lower valence states of linear polyenes: Locations and identifications

Contact Info

Product

Resources

About