title: Development of ultralow energy (1-10 eV) ion scattering spectrometry coupled with reflection absorption infrared spectroscopy and temperature programmed desorption for the investigation of molecular solids.
abstract: Extremely surface specific information, limited to the first atomic layer of molecular surfaces, is essential to understand the chemistry and physics in upper atmospheric and interstellar environments. Ultra low energy ion scattering in the 1-10 eV window with mass selected ions can reveal extremely surface specific information which when coupled with reflection absorption infrared (RAIR) and temperature programmed desorption (TPD) spectroscopies, diverse chemical and physical properties of molecular species at surfaces could be derived. These experiments have to be performed at cryogenic temperatures and at ultra high vacuum conditions without the possibility of collisions of neutrals and background deposition in view of the poor ion intensities and consequent need for longer exposure times. Here we combine a highly optimized low energy ion optical system designed for such studies coupled with RAIR and TPD and its initial characterization. Despite the ultralow collision energies and long ion path lengths employed, the ion intensities at 1 eV have been significant to collect a scattered ion spectrum of 1000 counts/s for mass selected CH2(+).
authors: DST Unit of Nanoscience (DST UNS), Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India.
authors: Soumabha
authors: S
authors: Bag
authors: DST Unit of Nanoscience (DST UNS), Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India.
authors: Radha Gobinda
authors: RG
authors: Bhuin
authors: DST Unit of Nanoscience (DST UNS), Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India.
authors: Rabin Rajan J
authors: RR
authors: Methikkalam
authors: DST Unit of Nanoscience (DST UNS), Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India.
authors: T
authors: T
authors: Pradeep
authors: Extrel CMS, LLC, 575 Epsilon Drive, Pittsburgh, Pennsylvania 15238, USA.
authors: Luke
authors: L
authors: Kephart
authors: Extrel CMS, LLC, 575 Epsilon Drive, Pittsburgh, Pennsylvania 15238, USA.
authors: Jeff
authors: J
authors: Walker
authors: Extrel CMS, LLC, 575 Epsilon Drive, Pittsburgh, Pennsylvania 15238, USA.
authors: Kevin
authors: K
authors: Kuchta
authors: Extrel CMS, LLC, 575 Epsilon Drive, Pittsburgh, Pennsylvania 15238, USA.
authors: Dave
authors: D
authors: Martin
authors: Extrel CMS, LLC, 575 Epsilon Drive, Pittsburgh, Pennsylvania 15238, USA.
authors: Jian
authors: J
authors: Wei