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The influence of vibronic coupling on the outer valence ionic states of cis-dichloroethene has been investigated by recording photoelectron spectra over the excitation range 19–90 eV using plane polarized synchrotron radiation, for two polarization orientations. The photoelectron anisotropy parameters and electronic state branching ratios derived from these spectra have been compared to theoretical predictions obtained with the continuum multiple scattering approach. This comparison shows that the photoionization dynamics of the à 2B2, B ̃ 2A1, C ̃ 2A2, and D ̃ 2B1 states, all of which are formed through the ejection of an electron from a nominally chlorine lone-pair orbital, exhibit distinct evidence of the Cooper minimum associated with the halogen atom. While retaining a high degree of atomic character, these orbital ionizations nevertheless display clear distinctions. Simulations, assuming the validity of the Born-Oppenheimer and the Franck-Condon approximations, of the X ̃ 2B1, à 2B2, and D ̃ 2B1 state photoelectron bands have allowed some of the vibrational structure observed in the experimental spectra to be assigned. The simulations provide a very satisfactory interpretation for the X ̃ 2B1 state band but appear less successful for the à 2B2 and D ̃ 2B1 states, with irregularities appearing in both. The B ̃ 2A1 and C ̃ 2A2 state photoelectron bands exhibit very diffuse and erratic profiles that cannot be reproduced at this level. Photoelectron anisotropy parameters, β, have been evaluated as a function of binding energy across the studied photon energy range. There is a clear step change in the β values of the à 2B2 band at the onset of the perturbed peak intensities, with β evidently adopting the value of the B ̃ 2A1 band β. The D ̃ 2B1 band β values also display an unexpected vibrational level dependence, contradicting Franck-Condon expectations. These various behaviors are inferred to be a consequence of vibronic coupling in this system. [ABSTRACT FROM AUTHOR]

The valence shell photoelectron spectrum of cis-dichloroethene has been studied both experimentally and theoretically. Photoelectron spectra have been recorded with horizontally and vertically plane polarized synchrotron radiation, thereby allowing the anisotropy parameters, characterizing the angular distributions, to be determined. The third-order algebraic-diagrammatic construction approximation scheme for the one-particle Green’s function has been employed to compute the complete valence shell ionization spectrum. In addition, the vertical ionization energies have been calculated using the outer valence Green’s function (OVGF) method and the equation-of-motion coupled-cluster, with single and double substitutions for calculating ionization potentials (EOM-IP-CCSD) model. The theoretical results have enabled assignments to be proposed for most of the structure observed in the experimental spectra, including the inner-valence regions dominated by satellite states. The linear vibronic coupling model has been employed to study the vibrational structure of the lowest photoelectron bands, using parameters obtained from ab initio calculations. The ground state optimized geometries and vibrational frequencies have been computed at the level of the second-order Møller-Plesset perturbation theory, and the dependence of the ionization energies on the nuclear configuration has been evaluated using the OVGF method. While the adiabatic approximation holds for the X ̃ 2B1 state photoelectron band, the A ̃ 2B2, B ̃ 2A1, and C ̃ 2A2 states interact vibronically and form a complex photoelectron band system with four distinct maxima. The D ̃ 2B1 and E ̃ 2B2 states also interact vibronically with each other. The potential energy surface of the D ̃ 2B1 state is predicted to have a double-minimum shape with respect to the out-of-plane a2 deformations of the molecular structure. The single photoelectron band resulting from this interaction is characterized by a highly irregular structure, reflecting the non-adiabatic nuclear dynamics occurring on the two coupled potential energy surfaces forming a conical intersection close to the minimum of the E ̃ 2B2 state. [ABSTRACT FROM AUTHOR]

Introduction: As rates of survival from cancer continue to increase in adolescents and young adults, long term physical and psychological impacts are likely to rise. For those diagnosed with cancer during childhood or adolescence, one such late effect may be delayed sexual development. Delayed sexual development may manifest as issues of sexual functioning (i.e., the ability to successfully complete the sexual response cycle) as well as issues of sexual self-concept (i.e., how one navigates the world as a sexual being). These issues may, in turn, impact survivors' self-esteem. These concerns are likely to be exponentially exacerbated when survivors identify as a member of a sexual and/or gender minority (SGM) group. Objective: Based on empirical research and two studies from our team, we examine variables that impact the sexual self-esteem of AYA cancer survivors, particularly those that identify as members of an SGM group. Methods: In our small pilot project, we conducted cognitive interviews to assess whether a novel model, adapted from sexual health frameworks established by Woods (1995) and Evan et al. (2006), applied to AYA cancer survivors. Following analysis of these interviews, we refined our model, and received funding for a larger qualitative study (n = 30) tailored to AYA cancer survivors who identify as members of an SGM group. Results: Four cisgender female cancer survivors participated in this small qualitative study, which provided preliminary validation that variables such as body image, amount of sexual education, quality of interpersonal relationships, and sexual functioning, were all tied into one's perception of their sexual self-esteem. Several additional potential variables were identified from these interviews, including amount of sexual equity (how much participants felt that their sexual activity was balanced between them and a partner), religiosity, negative self-evaluative emotions (e.g., guilt and shame), and SGM identity, that could influence sexual self-esteem. Preliminary analyses of our SGM-focused qualitative study have revealed high levels of asexuality and mental health comorbidities that may be affecting sexual self-esteem. Recruitment and analysis for this study is ongoing. Conclusions: Results from these two studies will provide some of the first empirical research on sexual self-esteem in a population for which sexual health is vastly under researched. We anticipate that this work will lay the foundation for novel measurements and interventions for these individuals. By providing a voice to those who are underrepresented in research, we hope that this research may have high-impact in informing future interventions to become more holistic and culturally-informed to allow for studies to ensure they are reflecting all identities of cancer survivors. Finally, we anticipate that this research may be of significant benefit to oncology providers and clinicians to overhaul and adapt sexual education for patients in treatment, as well as inform areas of concern and assessment for these providers and clinicians, particularly among their SGM patients and survivors. Disclosure: No. [ABSTRACT FROM AUTHOR]

The valence-shell ionization spectrum of bromobenzene, as a representative halogen substituted aromatic, was studied using the non-Dyson third-order algebraic-diagrammatic construction [nDADC(3)] approximation for the electron propagator. This method, also referred to as IP-ADC(3), was implemented as a part of the Q-Chem program and enables large-scale calculations of the ionization spectra, where the computational effort scales as n5 with respect to the number of molecular orbitals n. The IP-ADC(3) scheme is ideally suited for investigating low-lying ionization transitions, so fresh insight could be gained into the cationic state manifold of bromobenzene. In particular, the present IP-ADC(3) calculations with the cc-pVTZ basis reveal a whole class of low-lying low-intensity two-hole-one-particle (2h-1p) doublet and quartet states, which are relevant to various photoionization processes. The good qualitative agreement between the theoretical spectral profile for the valence-shell ionization transitions generated with the smaller cc-pVDZ basis set and the experimental photoelectron spectrum measured at a photon energy of 80 eV on the PLÉIADES beamline at the Soleil synchrotron radiation source allowed all the main features to be assigned. Some theoretical aspects of the ionization energy calculations concerning the use of various approximation schemes and basis sets are discussed. [ABSTRACT FROM AUTHOR]

Angle resolved photoelectron spectra of the X ²B1, Ã ²A2, B ²B1, and C ²B1 states of bromobenzene have been recorded over the excitation range 20.5-94 eV using linearly polarized synchrotron radiation. The photoelectron anisotropy parameters and electronic branching ratios derived from these spectra have been compared to theoretical predictions obtained with the continuum multiple scattering approach. This comparison shows that ionization from the 8b2 orbital and, to a lesser extent, the 4b1 orbital is influenced by the Cooper minimum associated with the bromine atom. The 8b2 and 4b1 orbitals are nominally bromine lone-pairs, but the latter orbital interacts strongly with the p-orbitals in the benzene ring and this leads to a reduced atomic character. Simulations of the X ²B1, B ²B2, and C ²B1 state photoelectron bands have enabled most of the vibrational structures appearing in the experimental spectra to be assigned. Many of the photoelectron peaks exhibit an asymmetric shape with a tail towards low binding energy. This asymmetry has been examined in the simulations of the vibrationally unexcited peak, due mainly to the adiabatic transition, in the X ²B1 state photoelectron band. The simulations show that the asymmetric profile arises from hot-band transitions. The inclusion of transitions originating from thermally populated levels results in a satisfactory agreement between the experimental and simulated peak shapes. [ABSTRACT FROM AUTHOR]

We report unambiguous experimental and theoretical evidence of intramolecular photoelectron diffraction in the collective vibrational excitation that accompanies high-energy photoionization of gas-phase CF4, BF3, and CH4 from the 1s orbital of the central atom. We show that the ratios between vibrationally resolved photoionization cross sections (v-ratios) exhibit pronounced oscillations as a function of photon energy, which is the fingerprint of electron diffraction by the surrounding atomic centers. This interpretation is supported by the excellent agreement between first-principles static-exchange and time-dependent density functional theory calculations and high resolution measurements, as well as by qualitative agreement at high energies with a model in which atomic displacements are treated to first order of perturbation theory. The latter model allows us to rationalize the results for all the v-ratios in terms of a generalized v-ratio, which contains information on the structure of the above three molecules and the corresponding molecular cations. A fit of the measured v-ratios to a simple formula based on this model suggests that the method could be used to obtain structural information of both neutral and ionic molecular species. [ABSTRACT FROM AUTHOR]

In this work, the characteristics of the plasma generated in HCl, KCl, and KOH solutions were analyzed using electrical and optical diagnostic techniques. Electrical discharges were initiated between two tungsten electrodes. Current and voltage characteristics have shown the features of a spark discharge for all of the solutions used in the experiment. The reactive species identified in the optical emission spectra depended on the type of solution used to generate the plasma. The time evolution of the reactive species depended on the nature of the solution and on the polarity of the applied pulse. The absorption spectra of the OH radical (X2Π → A2Σ+) were acquired when the voltage pulses were applied to the electrodes, with the intensity being lower in the regions between the pulses. The OH radical density was highest for the HCl solution plasma (2 × 1017 cm-3) when positive voltage pulses were applied to the electrodes. [ABSTRACT FROM AUTHOR]

We have studied the ultrafast dissociation of the H2S molecule upon S 2p3/2→6a1 inner-shell excitation by combining high-resolution resonant Auger spectroscopy and energy-selected Auger electron–ion coincidence measurements. Auger final states have been correlated to the different fragmentation pathways (S+, HS+, and H2S+ ions). As an original result, we evidence a three-step mechanism to describe the resonant production of S+: the Auger recombination in the HS* fragment is followed for the A 3Π and c 1Π states by the S++H fragmentation mechanism. [ABSTRACT FROM AUTHOR]

X-ray photoelectron spectroscopy and Auger spectroscopy studies of gas-phase hexamethyldisiloxane (HMDSO) are presented. The photodissociation of this molecule is studied using various experimental coincidence techniques. We compare the fragmentation pathways observed after core ionization followed by Auger decay and after valence double photoionization of the molecule. A strongly selective production of the doubly charged tetramethyldisiloxane ion is observed in the low binding-energy regions. Theoretical calculations are carried out to tentatively explain the stability of the produced dication. [ABSTRACT FROM AUTHOR]

To get further insight into the CH2BrCl site-selective fragmentation previously observed upon inner-shell ionization, we have performed high-resolution Br 3d and Cl 2p Auger and spin-orbit resolved Br 3d Auger spectra, and studied the dissociation properties of the CH2BrCl2+ dication formed at threshold by means of threshold electron pair-ion coincidence measurements. The key point is that the origin of site-specific bond breaking is found in the Auger decay itself, as it preferentially populates selected dication states. Whereas the predominance of the C[Single_Bond]Br bond breaking is observed in both threshold and inner-shell studies, no signature of selective C[Single_Bond]Cl rupture is reported for the dication formed at threshold. [ABSTRACT FROM AUTHOR]

Vibrationally resolved C1s and S2p photoelectron spectra of the thiophene molecule have been recorded using monochromated synchrotron radiation at photon energies of 330 eV and 210 eV, respectively. The photoelectron bands contain complex vibrational structures which are analyzed using ab initio and curve-fitting procedures. The analysis is in good agreement with the experimental spectrum which enables identification of two chemically shifted carbon 1 s core hole states. We were also able to determine the molecular-field splitting of the S2p [sub 3/2] ionic state to about 99 meV. The molecular-field splitting was moreover calculated using second-order Moller-Plesset perturbation theory, confirming the result from the fitting procedure. [ABSTRACT FROM AUTHOR]