Photoelectron circular dichroism of O 1s-photoelectrons of uniaxially oriented trifluoromethyloxirane: energy dependence and sensitivity to molecular configuration

Nalin, Giammarco; Fehre, K.; Trinter, Florian; Novikovskiy, N. M.; Anders, Nils; Trabert, D.; Grundmann, Sven; Kircher, Max; Khan, Arnab; Tomar, Raghu; Hofmann, M.; Waitz, M.; Vela-Peréz, Isabel; Kastirke, Gregor; Siebert, Juliane; Tsitsonis, D.; Fukuzawa, H.; Ueda, Kiyoshi; Williams, Joshua; Kargin, Denis; Maurer, Martin; Küstner-Wetekam, Catmarna; Marder, Lutz; Viehmann, J.; Knie, André; Jahnke, T.; Ilchen, Markus; Dørner, R.; Pietschnig, Rudolf; Demekhin, Ph. V.; Schöffler, M. S.

doi:10.1039/d1cp02462k

Cited by 15 publications

(36 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To access this molecular fragmentation axis, the Coulomb explosion into two charged fragments was investigated, following the procedure developed in previous publications. 11,12 For the oxygen atom, the combined fragmentation channels CF 3 + (m/q = 69)-C 2 H 3 O + (m/q = 43) and CF 3 + (m/q = 69)-C 2 H 2 O + (m/q = 42) were used in our previous work 12 to access PECD(cos y,cos b). However, for the 3F-emitters, these two fragmentation channels are strongly suppressed (about 75% weaker as compared to the O-case).…”

Section: Resultsmentioning

confidence: 99%

“…Therefore, the molecular orientation axis at the instant of the photoionization process was used as a free parameter when comparing the measured data to the calculations. 11,12 At first, the angle-resolved photoionization spectra were generated for different spatial orientations of the assumed fragmentation axis with respect to the light propagation direction, which are defined by the two Euler angles a o and b o . Since only one fragmentation direction is detected in the experiment, the computed spectra were then numerically integrated over the orientation angle a o to simulate a uniaxially oriented molecule.…”

Section: Experiments and Theorymentioning

confidence: 99%

See 1 more Smart Citation

Influence of the emission site on the photoelectron circular dichroism in trifluoromethyloxirane

Fehre

Trinter

Novikovskiy

et al. 2022

Phys. Chem. Chem. Phys.

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Experiments and Theorymentioning

confidence: 99%

Influence of the emission site on the photoelectron circular dichroism in trifluoromethyloxirane

Fehre

Trinter

Novikovskiy

et al. 2022

Phys. Chem. Chem. Phys.

Self Cite

View full text Add to dashboard Cite

show abstract

“…The quasi-collinear geometry of these laser sources with a linear and a circular polarization breaks the axial symmetry at the sample, raising issues when processing the 2D VMI data using an Abel inversion technique, which presupposes this symmetry. While alternative detection methods, such as fast time and position sensitive detection [17,19,28] or tomographic reconstruction [24,29] allow measuring the full 3D distribution without Abel inversion, for technical reasons their use was unfeasible in the present situation. However, as discussed in Sec.…”

Section: (D)mentioning

confidence: 98%

“…Compared to valence PECD, core-level PECD thus provides a powerful and direct enantio-sensitive probe of the electronic scattering potential of a molecule that is both site-and chemical-specific, and thus more sensitive to the electronic and structural environment surrounding the initial localized core state. The application of core-level PECD spectroscopy to the study of chirality of molecules in their ground state has proven to be a very sensitive tool to investigate the structure of molecules [11][12][13][14][15][16][17][18][19][20]. However, time-resolved core-level PECD studies clearly require the use of ultrashort, circularly polarized X-ray probe pulses, and such developments have been restricted by the limited availability of suitable high-brilliance sources in the soft X-ray range.…”

Section: Introductionmentioning

confidence: 99%

Time-resolved chiral X-Ray photoelectron spectroscopy with transiently enhanced atomic site-selectivity: a Free Electron Laser investigation of electronically excited fenchone enantiomers

Faccialà¹,

M.²,

Beauvarlet³

et al. 2022

Preprint

View full text Add to dashboard Cite

Chiral molecules are widespread in nature, playing a fundamental role in bio-chemical processes and in the origin of life itself. The observation of dynamics in chiral molecules is crucial for the understanding and control of the chiral activity of photo-excited states. One of the most promising techniques for the study of photo-excited chiral systems is time-resolved photoelectron circular dichroism (TR-PECD), which offers an intense and sensitive probe for vibronic and geometric molecular structure as well as electronic structures, and their evolution on a femtosecond timescale.However, the non-local character of the PECD effect, which is imprinted during the electron scattering off the molecule, makes the interpretation of TR-PECD experiments challenging. In this respect, core-photoionization is known to allow site-and chemical-sensitivity to photelectron spectroscopy. Here we demonstrate that TR-PECD utilising core-level photoemission enables probing the chiral electronic structure and its relaxation dynamics with atomic site sensitivity. Following UV pumped excitation to a 3s Rydberg state, fenchone enantiomers (C 10 H 16 O) were probed on a femtosecond scale using circularly polarized soft X-ray light pulses provided by the free-electron laser FERMI. C 1s binding energy shifts caused by the redistribution of valence electron density in this 3s-valence-Rydberg excitation allowed us to measure transient PECD chiral responses with an enhanced C-atom site-selectivity compared to that achievable in the ground state molecule.These results represent the first chemical-specific and site-specific, enantio-sensitive observations on the electronic structure of a photo-excited chiral molecule and pave the way towards chiral femtochemistry probed by core-level photoemission.I.

show abstract

“…The differential PECD for both R-TFMOx and S-MOx enantiomers is described as a function of the uniaxial orientation , as shown for both enantiomers in β 88 The experimental data are the combination diatomic breakup channels CF3 + (m/q = 69) -C2Hi = 1, 2, 3O + (m/q = 41, 42, 43). Image reproduced from [160].…”

Section: Influence Of Substitutional Groupsmentioning

confidence: 99%

An investigation of photoelectron angular distributions and circular dichroism of chiral molecules

Nalin¹

Self Cite

View full text Add to dashboard Cite

The present work demonstrates the capability of several type of molecular frame photoelectron angular distributions (MFPADs) and their linked chiroptical phenomenon the photoelectron circular dichroism (PECD) to map in great detail the molecular geometry of polyatomic chiral molecules as a function of photoelectron energy. To investigate the influence of the molecular potential on the MFPADs, two chiral molecules were selected, namely 2-(methyl)oxirane (C3H6O, MOx, m = 58,08 uma) and 2-(trifluoromethyl)oxirane (C3H3F3O, TFMOx, m = 112,03 uma). The two molecules differs in one substitutional group and share an oxirane group where the O(1s) electron was directly photoionized with the use of synchrotron radiation in the soft X-ray regime. The direct photoionization of the K-shell electron is well localized in the molecule and it induces the ejection of two or more electrons; the excited system separates into several charged (and eventually neutral) fragments which undergo Coulomb explosion due to their charges. The electrons and the fragments were detected using the COLd Target Recoil Ion Momentum Spectroscopy (COLTRIMS) and the momentum vectors calculated for each fragment belonging from a single ionization. The former method gives the possibility to post-orient molecules in space, giving access to the molecular frame, thus the MFPAD and its related PECD for multiple light propagation direction. Stereochemistry (from the Greek στερεο- stereo- meaning solid) refers to chemistry in three dimensions. Since most molecules show a three-dimensional structure (3D), stereochemistry pervades all fields of chemistry and biology, and it is an essential point of view for the understanding of chemical structure, molecular dynamics and molecular reactions. The understanding of the chemistry of life is tightly bounded with major discoveries in stereochemistry, which triggered tremendous technical advancements, making it a flourishing field of research since its revolutionary introduction in late 18th century. In chemistry, chirality is a brunch of stereochemistry which focuses on objects with the peculiar geometrical property of not being superimposable to their mirror-images. The word chirality is derived from the Greek χειρ for “hand”, and the first use of this term in chemistry is usually attributed to Lord Kelvin who called during a lecture at the Oxford University Junior Scientific Club in 1893 “any geometrical figure, or group of points, “chiral”, and say that it has chirality if its image in a plane mirror, ideally realized, cannot be brought to coincide with itself.”. Although the latter is usually considered as the birth of the word chirality, the concept underlying it was already present in several fields of science (above all mathematics), already proving the already multidisciplinary relevance of chirality across many field of science and beyond. Nature shows great examples of chiral symmetry on all scales. Empirically, it is possible to observe it at macroscopic scale (e.g. distribution of rotations of galaxies), down to the microscopic scale (e.g. structure of some plankton species), but it is at the molecular level where the number gets remarkable: most of the pharmaceutical drugs, food fragrances, pheromones, enzymes, amino acids and DNA molecules, in fact, are chiral. Moreover, the concept of chirality goes far beyond the mere spatial symmetry of objects being crucially entangled with the fundamental properties of physical forces in nature. The symmetry breaking, namely the different physical behaviour of a two chiral systems upon the same stimuli, is considered to be one of the best explanation for the long standing questions of homochirality in biological life, and ultimately to the chemical origin of life on Earth as we know it. Our organism shows high enantio-selectivity towards specific compounds ranging from drugs, to fragrances. Over 800 odour molecules commonly used in food and fragrance industries have been identified as chiral and their enantiomeric forms are perceived to have very different smells, as the well-know example of D- and L- limonene. Similarly, responses to pharmaceuticals drugs can be enantiomer specific, and in fact about 60 % the drugs currently on the market are chiral compounds, and nearly 90 % of them are sold as racemates. The same degree of enantio-selectivity is observed in the communications systems of plants and insects. Plants produce lipophilic liquids with high vapour pressure called plant volatiles (PVs) which are synthesized via different enzymes called tarpene synthases that are usually chiral. Chiral molecules and chiral effects have a strong impact on all the fields of science with exciting developments ranging from stereo-selective synthesis based on heterogeneous enantioselective catalysis, to optoelctronics, to photochemical asymmetric synthesis, and chiral surface science, just to cite a few. Chiral molecules come in two forms called enantiomers. Their almost identical chemical and physical properties continue to pose technical challenges concerning the resolution of racemic mixtures, the determination of the enantiomeric excess, and the direct determination of the absolute configuration of an enantiomer. ...

show abstract

Photoelectron circular dichroism of O 1s-photoelectrons of uniaxially oriented trifluoromethyloxirane: energy dependence and sensitivity to molecular configuration

Abstract: The photoelectron circular dichroism (PECD) of the O 1s-photoelectrons of trifluoromethyloxirane (TFMOx) is studied experimentally and theoretically for different photoelectron kinetic energies. The experiments were performed employing circularly polarized synchrotron...

Cited by 15 publications

References 58 publications

Influence of the emission site on the photoelectron circular dichroism in trifluoromethyloxirane

Influence of the emission site on the photoelectron circular dichroism in trifluoromethyloxirane

Time-resolved chiral X-Ray photoelectron spectroscopy with transiently enhanced atomic site-selectivity: a Free Electron Laser investigation of electronically excited fenchone enantiomers

An investigation of photoelectron angular distributions and circular dichroism of chiral molecules

Contact Info

Product

Resources

About