Positrons and positronium in macromolecules: Consequences of different charge states

Yoshinori Kobayashi; Kiminori Sato; Masato Yamawaki; Koji Michishio; Toshitaka Oka; Masakazu Washio

doi:10.1016/j.radphyschem.2022.110590

Positrons and positronium in macromolecules: Consequences of different charge states

Yoshinori Kobayashi^*, Kiminori Sato, Masato Yamawaki^*, Koji Michishio, Toshitaka Oka, Masakazu Washio

^*Corresponding author for this work

School of Advanced Science and Engineering

Research output: Contribution to journal › Article › peer-review

1 Citation (Scopus)

Abstract

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.

Original language	English
Article number	110590
Journal	Radiation Physics and Chemistry
Volume	202
DOIs	https://doi.org/10.1016/j.radphyschem.2022.110590
Publication status	Published - 2023 Jan

Keywords

Free volume
Macromolecule
Polar group
Positron
Positronium
Trapping

ASJC Scopus subject areas

Radiation

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10.1016/j.radphyschem.2022.110590

Cite this

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title = "Positrons and positronium in macromolecules: Consequences of different charge states",

abstract = "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.",

keywords = "Free volume, Macromolecule, Polar group, Positron, Positronium, Trapping",

author = "Yoshinori Kobayashi and Kiminori Sato and Masato Yamawaki and Koji Michishio and Toshitaka Oka and Masakazu Washio",

note = "Funding Information: This work was supported by JSPS KAKENHI Grant Numbers 17K05123 , 20K12506 and 22H01240 . Publisher Copyright: {\textcopyright} 2022 Elsevier Ltd",

year = "2023",

month = jan,

doi = "10.1016/j.radphyschem.2022.110590",

language = "English",

volume = "202",

journal = "Radiation Physics and Chemistry",

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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

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 -

Positrons and positronium in macromolecules: Consequences of different charge states

Abstract

Keywords

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