title: Role of Gas Molecule Complexity in Environmental Electron Microscopy and Photoelectron Yield Spectroscopy.
abstract: Environmental scanning electron microscopy (ESEM) and environmental photoelectron yield spectroscopy (EPYS) enable electron imaging and spectroscopy of surfaces and interfaces in low-vacuum gaseous environments. The techniques are both appealing and limited by the range of gases that can be used to amplify electrons emitted from a sample and used to form images/spectra. However, to date only H2O and NH3gases have been identified as highly favorable electron amplification media. Here we demonstrate that ethanol vapor (CH3CH2OH) is superior to both of these and attribute its performance to its molecular complexity and valence orbital structure. Our findings improve the present understanding of what constitutes a favorable electron amplification gas and will help expand the applicability and usefulness of the ESEM and EPYS techniques.
authors.affiliation: School of Physics and Advanced Materials, University of Technology Sydney , Ultimo, NSW 2007, Australia.
authors.forename: Toby W
authors.initials: TW
authors.lastname: Shanley
authors.affiliation: School of Physics and Advanced Materials, University of Technology Sydney , Ultimo, NSW 2007, Australia.
authors.forename: Fadi
authors.initials: F
authors.lastname: Bonnie
authors.affiliation: School of Physics and Advanced Materials, University of Technology Sydney , Ultimo, NSW 2007, Australia.
authors.forename: John
authors.initials: J
authors.lastname: Scott
authors.affiliation: School of Physics and Advanced Materials, University of Technology Sydney , Ultimo, NSW 2007, Australia.
authors.forename: Milos
authors.initials: M
authors.lastname: Toth
keywords: MO theory; gases; instrumental methods; molecular properties; surface science; transport properties