RT Journal Article T1 Experimental and theoretical cross sections for positron scattering from the pentane isomers. A1 Chiari, Luca A1 Zecca, Antonio A1 Blanco Ramos, Francisco A1 Brunger, M. J. AB Isomerism is ubiquitous in chemistry, physics, and biology. In atomic and molecular physics, in particular, isomer effects are well known in electron-impact phenomena; however, very little is known for positron collisions. Here we report on a set of experimental and theoretical cross sections for low-energy positron scattering from the three structural isomers of pentane: normal-pentane, isopentane, and neopentane. Total cross sections for positron scattering from normal-pentane and isopentane were measured at the University of Trento at incident energies between 0.1 and 50 eV. Calculations of the total cross sections, integral cross sections for elastic scattering, positronium formation, and electronic excitations plus direct ionization, as well as elastic differential cross sections were computed for all three isomers between 1 and 1000 eV using the independent atom model with screening corrected additivity rule. No definitive evidence of a significant isomer effect in positron scattering from the pentane isomers appears to be present. (C) 2016 AIP Publishing LLC. PB American Institute of Physics SN 0021-9606 YR 2016 FD 2016-02-28 LK https://hdl.handle.net/20.500.14352/24467 UL https://hdl.handle.net/20.500.14352/24467 LA eng NO 1. Anderson E. K., Boadle R. A., Machacek J. R., Chiari L., Makochekanwa C., Buckman S. J., Brunger M. J., Garcia G., Blanco F., Ingolfsson O., and Sullivan J. P., “Low energy positron interactions with uracil—Total scattering, positronium formation, and differential elastic scattering cross sections,” J. Chem. 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G.G. and F.B. would like to acknowledge the Spanish Ministerio de Economia y Productividad (Project No. FIS2012-31230) and the European Science Foundation (COST Action Grants Nos. MP1002-Nano-IBCT and MC1301-CELINA) for financial support. Finally, L.C. thanks the Japan Society for the Promotion of Science for his fellowship. NO Ministerio de Economia y Competitividad (MINECO) NO European Science Foundation (COST Action) NO Japan Society for the Promotion of Science DS Docta Complutense RD 7 may 2024