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We have developed the polyatomic extension of a recently established (M. Gustafsson, J. Chem. Phys, 138, 074308 (2013)) classical theory of radiative association in the absence of electronic transitions. The cross section of the process is calculated by a quasiclassical trajectory method combined with the classical Larmor formula which can provide the radiated power in collisions. We have also proposed a double-layered Monte Carlo scheme for efficient computation of ro-vibrationally quantum state resolved cross sections for radiative association. Besides the method development, we also calculated and fitted the global potential energy and dipole surface for the H + CN collisions to test our polyatomic semiclassical method., Comment: 13 pages, 8 figures

A semicalssical method based on surface-hopping techniques is developed to model the dynamics of radiative association with electronic transitions in arbitrary polyatomic systems. It can be proven that our method is an extension of the established semiclassical formula used in the characterization of diatomic molecule- formation. Our model is tested for diatomic molecules. It gives the same cross sections as the former semiclassical formula, but contrary to the former method it allows us to follow the fate of the trajectories after the emission of a photon. This means that we can characterize the rovibrational states of the stabilized molecules: using semiclassial quantization we can obtain quantum state resolved cross sections or emission spectra for the radiative association process. The calculated semiclassical state resolved spectra show good agreement with the result of quantum mechanical perturbation theory. Furthermore our surface-hopping model is not only applicable for the description of radiative association but it can be use for semiclassical characterization of any molecular process where spontaneous emission occurs.

Reaction rate constants and cross sections are computed for the radiative association of carbon cations ($\text{C}^+$) and fluorine atoms ($\text{F}$) in their ground states. We consider reactions through the electronic transition $1^1\Pi \rightarrow X^1\Sigma^+$ and rovibrational transitions on the $X^1\Sigma^+$ and $a^3\Pi$ potentials. Semiclassical and classical methods are used for the direct contribution and Breit--Wigner theory for the resonance contribution. Quantum mechanical perturbation theory is used for comparison. A modified formulation of the classical method applicable to permanent dipoles of unequally charged reactants is implemented. The total rate constant is fitted to the Arrhenius--Kooij formula in five temperature intervals with a relative difference of $<3\:\%$. The fit parameters will be added to the online database KIDA. For a temperature of $10$ to $250\:\text{K}$, the rate constant is about $10^{-21}\:\text{cm}^3\text{s}^{-1}$, rising toward $10^{-16}\:\text{cm}^3\text{s}^{-1}$ for a temperature of $30{,}000\:\text{K}$., Comment: 7 pages, 3 figures

Web based writing platforms allowing for exchanges across the world are increasingly being used in education. These recent forms of textual practice are highly related to conditions offered by the technology, allowing users, who previously were primarily consumers, to become producers of text. This chapter investigates student interaction over a blog in an intercultural student exchange between native speakers and nonnative speakers of English in higher education analysing and interpreting poetry. The groups of students involved in this study belong not only to different academic disciplines, but also differ in terms of nationality and language background. In the blog posts, the students' cultural voices are heard, offering a meeting between very contrasting groups. Scrutinising the student postings, the threaded discussions show ways that students thematise content and meaning in the poems. The results show that there are a number of features at play in an intercultural environment where language and translation issues are prominent parts of the student discussions, offering extended perspectives to the students' initial views. Collaborative efforts in such a diverse environment are important when negotiating meaning and extending students' understanding of poetry. [For the complete volume, "Second Language Teaching and Learning with Technology: Views of Emergent Researchers," see ED574599.]