The Synergy Between Qualitative Theory, Quantitative Calculations, and Direct Experiments in Understanding, Calculating, and Measuring the Energy Differences Between the Lowest Singlet and Triplet States of Organic Diradicals


This article discusses qualitative theory, quantitative calculations, and direct experiments.

Creation Date: April 18, 2011
UNT College of Arts and Sciences
UNT Scholarly Works
Total Uses: 191
Past 30 days: 6
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Creator (Author):
Lineberger, W. Carl

University of Colorado;

Creator (Author):
Borden, Weston T., 1943-

University of North Texas;

Publisher Info:
Publisher Name: Royal Society of Chemistry
Place of Publication: [Cambridge, United Kingdom]
  • EmbargoUntil: April 18, 2012
  • Creation: April 18, 2011

This article discusses qualitative theory, quantitative calculations, and direct experiments.

Department: Chemistry

The synergy between qualitative theory, quantitative calculations, and direct experiments in understanding, calculating, and measuring the energy differences between the lowest singlet and triplet states of organic diradicals, 2011, 13, 11792-11813, DOI: 10.1039/C0CP02786C - Reproduced by permission of The Royal Society of Chemistry


Abstract: This Perspective describes research, carried out in the authors' labs over the past forty years, aimed at understanding, predicting, and measuring the singlet-triplet energy differences (∆Est) in diradicals. A theory for qualitatively predicting the ground states of diradicals and the use of Negative Ion Photoelectron Spectroscopy (NIPES) for measuring ∆Est are described. The application of this theory, ab initio calculations, and NIPES to the prediction and measurement of ∆Est in a wide variety of organic diradicals is detailed. Among the diradicals that are discussed in this Perspective are HN, CH3N, PhN, CH2, trimethylenemethane (TMM), oxyallyl (OXA), meta-benzoquinodimethane (MBQDM), meta-benzoquinone (MBQ), tetramethyleneethane (TME), 1,2,4,5-tetramethylenebenzene (TMB), and D8h COT were, in fact, collaborations between the research groups of the authors. These two projects both took advantage of the ability to NIPES to provide information about transition states. Transition-state spectroscopy was used to measure the cabonyl stretching frequency in the singlet state of OXA and to establish that D8h COT violates the strictest version of Hund's rule.

Physical Description:

45 p.

Keyword(s): qualitative theory | quantitative calculations | energy differences | organic diradicals
Source: Physical Chemistry Chemical Physics, 2011, Cambridge: Royal Society of Chemistry
UNT College of Arts and Sciences
UNT Scholarly Works
  • DOI: 10.1039/C0CP02786C
  • ARK: ark:/67531/metadc77117
Resource Type: Article
Format: Text
Access: Public
Publication Title: Physical Chemistry Chemical Physics
Volume: 13
Issue: 25
Page Start: 11792
Page End: 11813
Peer Reviewed: Yes