PMID- 37465875
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20231025
IS  - 1439-7641 (Electronic)
IS  - 1439-4235 (Linking)
VI  - 24
IP  - 20
DP  - 2023 Oct 17
TI  - Lutidyl Radical Photoelectron Spectra Reveal Additive Substituent Effects on 
      Benzyl Derivatives' Ionization Energy.
PG  - e202300359
LID - 10.1002/cphc.202300359 [doi]
AB  - Understanding how isomerism influences photoelectron spectra helps in the 
      assignment and analysis of reactive mixtures, especially for heterocycles with 
      numerous isomers. Threshold photoelectron spectra of lutidyl radical isomers, 
      i. e., benzyl derivatives with a nitrogen heteroatom and a methyl substituent, 
      are recorded using vacuum ultraviolet synchrotron radiation. The radicals are 
      produced by flash pyrolysis from aminomethyl methylpyridine precursors. 
      Experimental ionization energies are determined to be 7.54, 7.50, and 7.45 eV for 
      2,4-, 2,6- and 3,5-lutidyl, respectively, in excellent agreement with composite 
      method calculations. Franck-Condon simulations aid the TPES assignment but are 
      also shown to exhibit artifacts if large-amplitude motions, notably the methyl 
      internal rotation are assumed to be active in the double harmonic approximation. 
      Based on calculated adiabatic ionization energies (AIE) of benzyl, picolyl, and 
      xylyl radicals, the N and CH(3) substituent effects are found to be additive, 
      position-dependent and decrease in the para>ortho greater, similarmeta order in magnitude with 
      the nitrogen heteroatom increasing and the methyl substituent decreasing the AIE. 
      These effects are discussed in light of the charge distribution upon ionization. 
      The additivity of the substituent effects also helps predict the influence of 
      substituents on the binding energy of the unpaired electron in analogous 
      radicals.
CI  - (c) 2023 The Authors. ChemPhysChem published by Wiley-VCH GmbH.
FAU - Kanayama, Keisuke
AU  - Kanayama K
AUID- ORCID: 0000-0003-0529-1006
AD  - Laboratory for Synchrotron Radiation and Femtochemistry, Paul Scherrer Institute, 
      CH-5232, Villigen PSI, Switzerland.
AD  - Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba, 980-8577, 
      Sendai, Miyagi, Japan.
AD  - Graduate School of Engineering, Tohoku University, 6-6 Aramaki Aza Aoba, Aoba, 
      980-8579, Sendai, Miyagi, Japan.
FAU - Fernholz, Christin
AU  - Fernholz C
AD  - Laboratory for Synchrotron Radiation and Femtochemistry, Paul Scherrer Institute, 
      CH-5232, Villigen PSI, Switzerland.
FAU - Nakamura, Hisashi
AU  - Nakamura H
AUID- ORCID: 0000-0002-3158-370X
AD  - Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba, 980-8577, 
      Sendai, Miyagi, Japan.
FAU - Maruta, Kaoru
AU  - Maruta K
AUID- ORCID: 0000-0001-8869-4294
AD  - Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba, 980-8577, 
      Sendai, Miyagi, Japan.
FAU - Bodi, Andras
AU  - Bodi A
AUID- ORCID: 0000-0003-2742-1051
AD  - Laboratory for Synchrotron Radiation and Femtochemistry, Paul Scherrer Institute, 
      CH-5232, Villigen PSI, Switzerland.
FAU - Hemberger, Patrick
AU  - Hemberger P
AUID- ORCID: 0000-0002-1251-4549
AD  - Laboratory for Synchrotron Radiation and Femtochemistry, Paul Scherrer Institute, 
      CH-5232, Villigen PSI, Switzerland.
LA  - eng
GR  - 22J13787/JSPS KAKENHI/
PT  - Journal Article
DEP - 20230811
PL  - Germany
TA  - Chemphyschem
JT  - Chemphyschem : a European journal of chemical physics and physical chemistry
JID - 100954211
SB  - IM
OTO - NOTNLM
OT  - flash pyrolysis
OT  - ionization potentials
OT  - nitrogen heterocycles
OT  - reactive intermediates
OT  - synchrotron radiation
EDAT- 2023/07/19 06:43
MHDA- 2023/07/19 06:44
CRDT- 2023/07/19 04:15
PHST- 2023/07/18 00:00 [revised]
PHST- 2023/05/22 00:00 [received]
PHST- 2023/07/19 06:44 [medline]
PHST- 2023/07/19 06:43 [pubmed]
PHST- 2023/07/19 04:15 [entrez]
AID - 10.1002/cphc.202300359 [doi]
PST - ppublish
SO  - Chemphyschem. 2023 Oct 17;24(20):e202300359. doi: 10.1002/cphc.202300359. Epub 
      2023 Aug 11.