A5039864014- Advanced Chemical Physics Studies
- Atmospheric Ozone and Climate
- Spectroscopy and Laser Applications
- Quantum, superfluid, helium dynamics
- Phase Equilibria and Thermodynamics
- Molecular Spectroscopy and Structure
- Astrophysics and Star Formation Studies
- Atomic and Subatomic Physics Research
- Atmospheric chemistry and aerosols
- Cold Atom Physics and Bose-Einstein Condensates
- Spectroscopy and Quantum Chemical Studies
- High-pressure geophysics and materials
- Astro and Planetary Science
- Crystallography and molecular interactions
- Chemical Thermodynamics and Molecular Structure
- Inorganic Fluorides and Related Compounds
- Crystal structures of chemical compounds
- Copper-based nanomaterials and applications
- X-ray Diffraction in Crystallography
- Material Dynamics and Properties
- Inorganic and Organometallic Chemistry
- Crystallization and Solubility Studies
- Metal-Organic Frameworks: Synthesis and Applications
- Thermodynamic properties of mixtures
- Catalytic Processes in Materials Science
University of East London
2019-2023
University of Patras
2021-2023
Missouri University of Science and Technology
2021
Queen Mary University of London
2014-2020
Transnational Press London
2017
Laboratoire d’Etudes du Rayonnement et de la Matière en Astrophysique et Atmosphères
2013
Sorbonne Université
2009-2012
Centre National de la Recherche Scientifique
2009-2012
University of Oxford
2003-2012
Radboud University Nijmegen
2012
The BASECOL2012 database is a repository of collisional data and web service within the Virtual Atomic Molecular Data Centre (VAMDC, http://www.vamdc.eu). It contains rate coefficients for excitation rotational, ro-vibrational, vibrational, fine, hyperfine levels molecules by atoms, molecules, electrons, as well fine-structure some atoms that are relevant to interstellar circumstellar astrophysical applications. Submissions new published sets welcome, they will be critically evaluated before...
To understand how Phosphorus-bearing molecules are formed in star-forming regions, we have analysed ALMA observations of PN and PO towards the massive region AFGL 5142, combined with a new analysis data comet 67P/Churyumov-Gerasimenko taken ROSINA instrument onboard Rosetta. The maps show that emission arises from several spots associated low-velocity gas narrow linewidths cavity walls bipolar outflow. is more abundant than most spots, PO/PN ratio increasing as function distance to...
Context . The global context of making numerous data produced by researchers available requires collecting and organising the data, assigning meaningful metadata, presenting in a homogeneous way. BASECOL database, which collects inelastic rate coefficients for application to interstellar medium circumstellar cometary atmospheres, meets those requirements. Aims We aim present scientific content BASECOL2023 edition. Methods While previous versions relied on finding literature, current version...
Cu 2 O has been obtained via the thermal oxidation of foils with a maximum thickness 120 μm under Ar and at 1020°C for 30 min. Care was taken...
The depolarization of OH(X Π23/2,v=0,J=1.5–6.5,e) rotational angular momentum (RAM) in collisions with He and Ar under thermal conditions (298 K) has been studied using two-color polarization spectroscopy (PS). Orientation or alignment the OH RAM was achieved circularly linearly polarized pulsed excitation, respectively, on off-diagonal A Σ2+−X Π2(1,0) band. evolution ground-state OH(X) polarization, exclusively, probed an independent, pulse tuned to diagonal Π2(0,0) PS signal decay rate...
Zeeman quantum beat spectroscopy has been used to measure the 300 K rate constants for angular momentum depolarization of OH(A (2)Sigma(+)) in presence Ar. We show that amplitude at short times, absence collisions, is well described by previously developed line strength theory (1+1) laser induced fluorescence. The subsequent pressure dependent decay extract and estimates collisional cross sections. Depolarization accompanies both inelastic giving rise rotational energy transfer, elastic...
One-colour polarization spectroscopy (PS) on the OH A 2Σ+ − X 2Π(0,0) band has been used to measure removal of bulk rotational angular momentum alignment ground-state OH(X 2Π) in collisions with He and Ar. Pseudo-first-order PS signal decays at different collider partial pressures were determine second-order decay rate constants for 2Π3/2, J = 1.5–6.5, e states. The constant, kPS, is sensitive all processes that remove population destroy polarization. contribution kPS from pure (elastic)...
Quasiclassical trajectory (QCT) and quantum mechanical (QM) close-coupling calculations have been used to study the state-resolved rotationally inelastic scattering of NO(X2Π1/2,v = 0,j 1/2,e/f) by He on most recent ab initio potential energy surface J. Kłos et al. [J. Chem. Phys. 2000, 112, 2195.]. Opacity functions, integral differential cross sections are reported at collision energies 63 147 meV compared with previous theoretical experimental measurements this other systems. The...
Quantum mechanical close-coupling calculations have been used to obtain fully quantum state-resolved differential cross sections and opacity functions for the rotationally inelastic collisions of NO(XΠ2) with He at collision energies 63 147meV using most recent ab initio potential energy surfaces Kłos et al. [J. Chem. Phys. 112, 2195 (2000)]. Double peaks observed in Λ-doublet resolved are shown be related presence analogous corresponding functions. These structures can linked directly a...
We present a new set of three-dimensional potential energy surfaces (PES) for the OH(X(2)Π)-He van der Waals system, which explicitly takes into account OH vibrational motion. Ab initio calculations OH-He PES were carried out using open-shell single- and double-excitation coupled cluster approach with non-iterative perturbational treatment triple excitations [RCCSD(T)]. The augmented correlation-consistent aug-cc-pVXZ (X = Q, 5, 6) basis sets employed, energies obtained then extrapolated to...
The physics of supercritical states is understood to a much lesser degree compared subcritical liquids. Carbon dioxide, in particular, has been intensely studied, yet little known about the part its phase diagram. Here, we combine neutron scattering experiments and molecular dynamics simulations demonstrate structural crossover at Frenkel line. seen pressures as high 14 times critical pressure evidenced by changes main features structure factor pair distribution functions.
We show that weak residual magnetic fields can significantly affect the preparation and measurement of molecular rotational angular momentum alignment in a typical gas-phase stereodynamics apparatus. Specifically, polarization spectroscopy, third-order nonlinear spectroscopic technique, is used to prepare probe collisional noncollisional losses OH X (2)Pi. Residual order geomagnetic field are shown have significant effect on prepared submicrosecond timescale. This be expected for many free...
We present a new set of potential energy surfaces (PESs) for the CH(X(2)Π)-He van der Waals system. Ab initio calculations CH-He PES were carried out using open-shell single- and double-excitation coupled cluster approach with non-iterative perturbational treatment triple excitations [RCCSD(T)]. The augmented correlation-consistent polarized valence quadruple-zeta (aug-cc-pVQZ) basis was employed by mid-bond functions. Integral cross sections rotational excitation in collisions calculated...
The depolarization of the rotational angular momentum electronically excited OH(2Σ) radicals through collisions with water molecules has been measured using Zeeman quantum beat spectroscopy. new data have permitted evaluation OH(A) state-specific quenching and cross-sections for superthermal mean relative velocities centred around 3500 m s-1. are compared both values available in literature, predictions based on a simple harpoon model, found to be good qualitative accord previous findings....
We have applied the polarisation spectroscopy (PS) technique to collisional depolarisation of selected OH (X(2)Pi, v = 0, F(1), J 1.5 and 4.5, e) levels by Xe at room temperature (nominally 298 K). The measured total rate constants, k, are combination population transfer out initial level elastic tensor moment respective rank K 1 (orientation) or 2 (alignment) its angular momentum distribution. Neither k is strongly J-dependent. consistently larger than as expected for |J,m(J)--> |J,m'(J)...
Rotational excitation of interstellar PN molecules induced by collisions with H2 is investigated. We present the first ab initio four-dimensional potential energy surface (PES) for PN–H2 van der Waals system. The PES was obtained using an explicitly correlated coupled cluster approach single, double, and perturbative triple excitations [CCSD(T)-F12b]. method interpolating moving least squares used to construct analytical from these data. equilibrium structure complex found be linear, aligned...
The absolute value of the cross section for abstraction reaction between fast H atoms and H2O has been determined experimentally at a mean collision energy 2.46 eV. OH population distribution same also determined. new measurements are compared with state-of-the-art quantum mechanical quasiclassical scattering calculations on most recently developed potential surface.
The depolarisation of selected OH (X2Π3/2v = 0, J 1.5 and 4.5, e) levels in collisions with the molecular partners N2 O2 at room temperature (nominally 298 K) has been studied using polarisation spectroscopy (PS) technique. We obtain total rate constants, k(K)PS, which are combination population transfer out initial level elastic tensor moment respective rank K 1 (orientation) or 2 (alignment) its angular momentum distribution. causes more rapid decay PS signals than O2. There no clear...
We present the first ab initio potential energy surfaces (PESs) for PO(X2Π)-He van der Waals system. The PESs were obtained using open-shell partially spin-restricted coupled cluster approach with single, double and perturbative triple excitations [UCCSD(T)]. augmented correlation-consistent polarized valence triple-zeta (aug-cc-pVTZ) basis set was employed supplemented by mid-bond functions. Integral differential cross sections rotational excitation in PO-He collisions calculated new PES...
Infrared, Raman, UV-VIS, 1 H and 13 C NMR spectroscopic properties of 1-Methylbenzotriazole (MEBTA) are reported using experimental computational methods.Density functional theory (DFT) various basis sets was employed to model the data.The vibrational data were in very good agreement with DFT predictions.The 6-311+G(d,p) set found be adequate for this study conjunction B3LYP, BP86, CAM-B3LYP functionals.The effects solvation MEBTA solvents also investigated UV-VIS experiments...
Abstract Hyperfine-resolved collisions between OH radicals and He atoms are investigated using quantum scattering calculations the most recent ab initio potential energy surface, which explicitly takes into account vibrational motion. Such play an important role in astrophysics, particular modelling of masers. The hyperfine-resolved collision cross sections calculated for energies up to 2500 cm -1 from nuclear spin free S -matrices a recoupling technique. collisional hyperfine propensities...