TY - JOUR
T1 - Positrons and positronium in macromolecules
T2 - Consequences of different charge states
AU - Kobayashi, Yoshinori
AU - Sato, Kiminori
AU - Yamawaki, Masato
AU - Michishio, Koji
AU - Oka, Toshitaka
AU - Washio, Masakazu
N1 - Funding Information:
This work was supported by JSPS KAKENHI Grant Numbers 17K05123 , 20K12506 and 22H01240 .
Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2023/1
Y1 - 2023/1
N2 - Because of their different charge states, positrons and positronium (Ps) behave quite differently in macromolecules. The behavior of positively charged positrons is strongly influenced by electrostatic interactions. In nonpolar macromolecules such as polyethylene, energetic positrons, if not incorporated into Ps, fall into a delocalized state. These positrons are sensitively trapped by polar groups, if any. On the other hand, charge-neutral Ps is localized in a free volume regardless of the macromolecule's chemical structure. In this study, we discuss the behavior and annihilation characteristics of positrons and Ps in various macromolecules, emphasizing their differences.
AB - Because of their different charge states, positrons and positronium (Ps) behave quite differently in macromolecules. The behavior of positively charged positrons is strongly influenced by electrostatic interactions. In nonpolar macromolecules such as polyethylene, energetic positrons, if not incorporated into Ps, fall into a delocalized state. These positrons are sensitively trapped by polar groups, if any. On the other hand, charge-neutral Ps is localized in a free volume regardless of the macromolecule's chemical structure. In this study, we discuss the behavior and annihilation characteristics of positrons and Ps in various macromolecules, emphasizing their differences.
KW - Free volume
KW - Macromolecule
KW - Polar group
KW - Positron
KW - Positronium
KW - Trapping
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U2 - 10.1016/j.radphyschem.2022.110590
DO - 10.1016/j.radphyschem.2022.110590
M3 - Article
AN - SCOPUS:85140138664
SN - 0969-806X
VL - 202
JO - Radiation Physics and Chemistry
JF - Radiation Physics and Chemistry
M1 - 110590
ER -