J. Mass Spectrom. Soc. Jpn.

Vol. 58, No. 1, 2010

COMMENTARY  4   !"Fundamentals of Mass Spectrometry
ῌFundamental Aspects of Photoionization of Moleculesῌ1῎2
Kenichiro T6C6@61῎ and Inosuke KDN6CD2
1

 RIKEN SPring-8, Sayo, Sayo-gun, HYOGO,JAPAN2    Professor Emeritus of University of Hyogo

Fundamental aspects of molecular photoionization are described in comparison with electron ionization,emphasizing the di#erence in the threshold behavior.
(Received May 25, 2009; Accepted May 25, 2009)

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/4*+ yzL-{*a +p|+ Kr 1,236 Å (10.03 eV), 1,165 Å (10.64 eV)

D!A#o6Ae0}& ./

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῎ Correspondence to: Kenichiro T6C6@6, RIKEN SPring-8,
1῍1῍1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679῍5148, JAPAN,
e-mail: kentanaka@spring8.or.jp+
+ »679῍5148 ¼½¼D E 1῍1῍1^P_-wbµ4¶J·ªD&6 b# m$+F./-c4*+ 4]^P_D±² ³%@3FD./-¸= >~&bw ;&6 C- FD%J|J©-4]^P_4B´¹&w+ ºA#o F

ῌ 13 ῌK. Tanaka and I. Koyanon,l$¼0

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xT n 

, [KR 7m

 uv~ [8 tJLῌ 15 ῌ!"&=»,

K. Tanaka and I. Koyano

G#$  /0123(w,QZ\Q

3. ῌ ῏ ῎ ῍|}~^e  3!"#$  %&'() *+",-.

456

/012378 

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YZ[Z 10.51, 13.13, 13.25 eV -

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2)

3)
4)
5)

Qugvw/0123JKPXQ#$bH-A mnopq6)

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Q"OP{Z©¥Tῑ

4Af,g 10 eV cdh,ijkl(+. Yv".

7 (-cd7Qe /0123( mnopq

&(" ^~

8OP (photo ionization detector; PID) D Q V xZj sPX/0123
]rHh 70 eV /0123(gG{ZJK-.

4JKLMNL eV OP N7 C }¡{Z". OP

4 56

7 @A,BC D, /0123EF6

7/0123

9:;< => ?" Az,. b   ῐF. P. Lossing and I. Tanaka, J. Chem. Phys., 25, 1031
(1956).
ª«¬­® ¯°§ ±§²³ 11´ µ¶·¸ ] P¹ º» (1987) ¼ 10 ½ p. 285.
G. H. Wannier, Phys. Rev., 90, 817 (1953).
U. Fano, Phys. Rev., 124, 1866 (1961).
H. Hurzeler, M. G. Inghram, and J. D. Morrison, J. Chem.
Phys., 28, 76 (1958).
W. A. Chupka, J. Berkowitz, and K. M. A. Refaey, J.
Chem. Phys., 50, 1938 (1969).

Keywords: Photoionization, Electron ionization, Ionization
e$ciency curve, Threshold law`a( xQxQyz . {Kῌ 16 ῌ