Megan R Bentley, Peter R Franke, Kaila E Weflen, David H Bross, Branko Ruscic, John F Stanton
{"title":"NF3电离能测定的理论与实验差异。","authors":"Megan R Bentley, Peter R Franke, Kaila E Weflen, David H Bross, Branko Ruscic, John F Stanton","doi":"10.1021/acs.jpca.5c00613","DOIUrl":null,"url":null,"abstract":"<p><p>High-accuracy <i>ab initio</i> thermochemical predictions for the ionization energy of NF<sub>3</sub>, the barrier height (to inversion) of NF<sub>3</sub><sup>+</sup>, and the dissociative ionization threshold of NF<sub>3</sub> to NF<sub>2</sub><sup>+</sup> + F are presented and incorporated into Active Thermochemical Tables. The adiabatic ionization energy of the first ionization band of NF<sub>3</sub>, calculated at 12.647 ± 0.010 eV, is at odds with previous experimental interpretations by nearly 0.36 eV due to unfavorable Franck-Condon factors associated with this transition. The barrier (to inversion) height is calculated to be about 0.6 eV lower in energy than the prior interpretation, which instigates a discussion of the supposed vibrational structure of the first ionization band of NF<sub>3</sub>. Updated assignments of the photoelectron spectrum are proposed, and the loss in vibrational spacing on the high-energy side of the experimental ionization band is discussed. Rudimentary anharmonic Franck-Condon simulations qualitatively reproduce the broad spectral features observed in experiment.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":""},"PeriodicalIF":2.7000,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Discrepancies between Theory and Experiment in Determining the Ionization Energy of NF<sub>3</sub>.\",\"authors\":\"Megan R Bentley, Peter R Franke, Kaila E Weflen, David H Bross, Branko Ruscic, John F Stanton\",\"doi\":\"10.1021/acs.jpca.5c00613\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>High-accuracy <i>ab initio</i> thermochemical predictions for the ionization energy of NF<sub>3</sub>, the barrier height (to inversion) of NF<sub>3</sub><sup>+</sup>, and the dissociative ionization threshold of NF<sub>3</sub> to NF<sub>2</sub><sup>+</sup> + F are presented and incorporated into Active Thermochemical Tables. The adiabatic ionization energy of the first ionization band of NF<sub>3</sub>, calculated at 12.647 ± 0.010 eV, is at odds with previous experimental interpretations by nearly 0.36 eV due to unfavorable Franck-Condon factors associated with this transition. The barrier (to inversion) height is calculated to be about 0.6 eV lower in energy than the prior interpretation, which instigates a discussion of the supposed vibrational structure of the first ionization band of NF<sub>3</sub>. Updated assignments of the photoelectron spectrum are proposed, and the loss in vibrational spacing on the high-energy side of the experimental ionization band is discussed. Rudimentary anharmonic Franck-Condon simulations qualitatively reproduce the broad spectral features observed in experiment.</p>\",\"PeriodicalId\":59,\"journal\":{\"name\":\"The Journal of Physical Chemistry A\",\"volume\":\" \",\"pages\":\"\"},\"PeriodicalIF\":2.7000,\"publicationDate\":\"2025-04-04\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"The Journal of Physical Chemistry A\",\"FirstCategoryId\":\"1\",\"ListUrlMain\":\"https://doi.org/10.1021/acs.jpca.5c00613\",\"RegionNum\":2,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"CHEMISTRY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"The Journal of Physical Chemistry A","FirstCategoryId":"1","ListUrlMain":"https://doi.org/10.1021/acs.jpca.5c00613","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
Discrepancies between Theory and Experiment in Determining the Ionization Energy of NF3.
High-accuracy ab initio thermochemical predictions for the ionization energy of NF3, the barrier height (to inversion) of NF3+, and the dissociative ionization threshold of NF3 to NF2+ + F are presented and incorporated into Active Thermochemical Tables. The adiabatic ionization energy of the first ionization band of NF3, calculated at 12.647 ± 0.010 eV, is at odds with previous experimental interpretations by nearly 0.36 eV due to unfavorable Franck-Condon factors associated with this transition. The barrier (to inversion) height is calculated to be about 0.6 eV lower in energy than the prior interpretation, which instigates a discussion of the supposed vibrational structure of the first ionization band of NF3. Updated assignments of the photoelectron spectrum are proposed, and the loss in vibrational spacing on the high-energy side of the experimental ionization band is discussed. Rudimentary anharmonic Franck-Condon simulations qualitatively reproduce the broad spectral features observed in experiment.
期刊介绍:
The Journal of Physical Chemistry A is devoted to reporting new and original experimental and theoretical basic research of interest to physical chemists, biophysical chemists, and chemical physicists.