Evaluation of the inelastic mean free path (IMFP) of electrons in polyaniline and polyacetylene samples obtained from elastic peak electron spectroscopy (EPES)

• Authors: György Gergely , Miklós Menyhard , Attila Sulyok , Sándor Gurban , Beata Lesiak , Aleksander Jablonski , Andrzej Kosinski , József Toth , Dezső Varga
• Languages of publication: EN

Abstracts

EN

The inelastic mean free path (IMFP) of electrons was determined experimentally for selected polyaniline and polyacetylene samples with Ag and Ni references using elastic peak electron spectroscopy (EPES). The surface composition was determined by XPS and density by helium pycnometry. The high resolution hemispherical ESA-31 and ADES-400 spectrometers were used for measurements in the energy range E = 0.5–3.0 keV and E =0.4 − 1.6 keV, respectively. The integrated elastic peak intensity ratios for sample and reference were calculated using the Monte Carlo (MC) algorithm based on the electron elastic scattering cross-sections database NIST SRD64 version 3.1 and applying TPP-2M IMFPs for polymers. Surface excitation parameters (SEP) and material parameters (ach) for polymers were determined, using the model of Chen, from comparison of measured and MC calculated elastic peak intensity ratios. These corrections proved to be efficient in decreasing the percentage deviations between the obtained IMFPs and the TPP-2M formula IMFPs. The elastic peak of hydrogen was observed in the EPES spectra of polymers. The experimental contribution of the hydrogen to the total elastic peak was 0.58%, while this value obtained from the MC simulations was 1.98%.

Keywords

EN

Polymers; surface excitation; EPES; IMFP

Discipline

• 36.20.-r: Macromolecules and polymer molecules
• 34.80.Bm: Elastic scattering

• Publisher: De Gruyter Open
• Journal: Open Physics
• Year: 2007
• Volume: 5
• Issue: 2
• Pages: 188-200

Dates

published

1 - 6 - 2007

online

1 - 6 - 2007

Contributors

author

György Gergely

• Research Institute for Technical Physics and Materials Sciences HAS, H-1525, Budapest, Hungary

author

Miklós Menyhard

• Research Institute for Technical Physics and Materials Sciences HAS, H-1525, Budapest, Hungary

author

Attila Sulyok

• Research Institute for Technical Physics and Materials Sciences HAS, H-1525, Budapest, Hungary

author

Sándor Gurban

• Research Institute for Technical Physics and Materials Sciences HAS, H-1525, Budapest, Hungary

author

Beata Lesiak

• Institute of Physical Chemistry PAS, 01-224, Warszawa, Poland

author

Aleksander Jablonski

• Institute of Physical Chemistry PAS, 01-224, Warszawa, Poland

author

Andrzej Kosinski

• Institute of Physical Chemistry PAS, 01-224, Warszawa, Poland

author

József Toth

• Institute of Nuclear Physics HAS, H-4001, Debrecen, Hungary

author

Dezső Varga

• Institute of Nuclear Physics HAS, H-4001, Debrecen, Hungary

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Identifiers

DOI

10.2478/s11534-007-0012-y