{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T05:35:06Z","timestamp":1776836106096,"version":"3.51.2"},"reference-count":77,"publisher":"AIP Publishing","issue":"21","content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2012,12,7]]},"abstract":"<jats:p>The Jahn-Teller (JT) coupling effects in the triply degenerate ground electronic state of methane radical cation are investigated theoretically within a quadratic vibronic coupling approach. The underlying potential energy surfaces over the two-dimensional space of nuclear coordinates, subject to the T2\u2009\u2297\u2009(e + t2 + t2) Jahn-Teller effect, are established from extensive ab initio calculations using the multi-reference configuration interaction method and then employed to determine the various parameters of a diabatic Hamiltonian of this system. Our previous investigation [T. Mondal and A. J. C. Varandas, J. Chem. Phys.\u2008135, 174304 (2011)10.1063\/1.3658641], relying on the linear vibronic coupling approach augmented by only a diagonal second-order term of the totally symmetric mode, are extended here by including all possible quadratic coupling constants of JT active e and t2 modes. Inclusion of these quadratic couplings is found to be important to reproduce correctly the broad vibrational structure and for a better description of dynamical JT effect in the first vibronic band of this radical cation. The impact of large amplitude motions (which are responsible for floppiness of the molecule) on the vibronic structure and dynamics of the first photoelectron band have been examined via readjustment of their linear coupling parameters up to \u00b110%.<\/jats:p>","DOI":"10.1063\/1.4768675","type":"journal-article","created":{"date-parts":[[2012,12,8]],"date-time":"2012-12-08T06:49:02Z","timestamp":1354949342000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":15,"title":["Quadratic coupling treatment of the Jahn-Teller effect in the triply-degenerate electronic state of $\\bf CH_4^+$CH4+: Can one account for floppiness?"],"prefix":"10.1063","volume":"137","author":[{"given":"T.","family":"Mondal","sequence":"first","affiliation":[{"name":"Universidade de Coimbra Departamento de Qu\u00edmica, , 3004-535 Coimbra, Portugal"}]},{"given":"A. J. C.","family":"Varandas","sequence":"additional","affiliation":[{"name":"Universidade de Coimbra Departamento de Qu\u00edmica, , 3004-535 Coimbra, Portugal"}]}],"member":"317","published-online":{"date-parts":[[2012,12,7]]},"reference":[{"key":"2023062520401590400_c1","doi-asserted-by":"publisher","first-page":"220","DOI":"10.1098\/rspa.1937.0142","volume":"161","year":"1937","journal-title":"Proc. R. Soc. London, Ser. A"},{"key":"2023062520401590400_c2a","doi-asserted-by":"publisher","first-page":"425","DOI":"10.1098\/rspa.1957.0010","volume":"238","year":"1957","journal-title":"Proc. R. Soc. London, Ser. A"},{"key":"2023062520401590400_c2b","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1098\/rspa.1958.0022","volume":"244","year":"1958","journal-title":"Proc. R. Soc. London, Ser. A"},{"key":"2023062520401590400_c2c","first-page":"429","volume":"2","year":"1961","journal-title":"Adv. Spectrosc."},{"key":"2023062520401590400_c3","volume-title":"The Jahn-Teller Effect in Molecules and Crystals","year":"1972"},{"key":"2023062520401590400_c4","doi-asserted-by":"publisher","first-page":"59","DOI":"10.1002\/9780470142813.ch2","volume":"57","year":"1984","journal-title":"Adv. Chem. Phys."},{"key":"2023062520401590400_c5a","volume-title":"The Jahn-Teller Effect","year":"2006"},{"key":"2023062520401590400_c5b","doi-asserted-by":"publisher","first-page":"1067","DOI":"10.1021\/cr0004411","volume":"101","year":"2001","journal-title":"Chem. Rev."},{"key":"2023062520401590400_c6a","doi-asserted-by":"publisher","first-page":"483","DOI":"10.1080\/01442350500037455","volume":"23","year":"2004","journal-title":"Int. Rev. Phys. Chem."},{"key":"2023062520401590400_c6b","doi-asserted-by":"publisher","first-page":"1004","DOI":"10.1021\/ar800186s","volume":"42","year":"2009","journal-title":"Acc. Chem. Res."},{"key":"2023062520401590400_c7","doi-asserted-by":"publisher","first-page":"139","DOI":"10.1016\/j.cplett.2010.01.032","volume":"487","year":"2010","journal-title":"Chem. Phys. Lett."},{"key":"2023062520401590400_c8","volume-title":"Theory of the Jahn-Teller Effect","author":"Quack","year":"2011"},{"key":"2023062520401590400_c9","doi-asserted-by":"publisher","first-page":"72","DOI":"10.1063\/1.1750327","volume":"7","year":"1939","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c10","doi-asserted-by":"publisher","first-page":"1251","DOI":"10.1103\/PhysRev.108.1251","volume":"108","year":"1957","journal-title":"Phys. Rev."},{"key":"2023062520401590400_c11","first-page":"91","volume-title":"Solid State Physics: Advances in Research and Applications","author":"Seitz","year":"1967"},{"key":"2023062520401590400_c12a","doi-asserted-by":"publisher","first-page":"407","DOI":"10.1103\/PhysRev.187.407","volume":"187","year":"1969","journal-title":"Phys. Rev."},{"key":"2023062520401590400_c12b","doi-asserted-by":"publisher","first-page":"1769","DOI":"10.1016\/0022-3697(69)90245-5","volume":"30","year":"1969","journal-title":"J. Phys. Chem. Solids"},{"key":"2023062520401590400_c12c","doi-asserted-by":"publisher","first-page":"6438","DOI":"10.1103\/PhysRevB.26.6438","volume":"26","year":"1982","journal-title":"Phys. Rev. B"},{"key":"2023062520401590400_c12d","doi-asserted-by":"publisher","first-page":"4054","DOI":"10.1063\/1.1726575","volume":"44","year":"1966","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c13","doi-asserted-by":"publisher","first-page":"8131","DOI":"10.1039\/c0cp02598d","volume":"13","year":"2011","journal-title":"Phys. Chem. Chem. Phys."},{"key":"2023062520401590400_c14","doi-asserted-by":"publisher","first-page":"6318","DOI":"10.1063\/1.459698","volume":"93","year":"1990","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c15","doi-asserted-by":"publisher","first-page":"449","DOI":"10.1016\/0009-2614(93)85100-3","volume":"201","year":"1990","journal-title":"Chem. Phys. Lett."},{"key":"2023062520401590400_c16","doi-asserted-by":"publisher","first-page":"042501","DOI":"10.1103\/PhysRevA.81.042501","volume":"81","year":"2010","journal-title":"Phys. Rev. A"},{"key":"2023062520401590400_c17","first-page":"442","volume":"269","year":"1962","journal-title":"Proc. R. Soc. London, Ser. A"},{"key":"2023062520401590400_c18","doi-asserted-by":"publisher","first-page":"73","DOI":"10.1063\/1.1673835","volume":"53","year":"1970","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c19","doi-asserted-by":"publisher","first-page":"113","DOI":"10.1080\/00268977100100121","volume":"20","year":"1971","journal-title":"Mol. Phys."},{"key":"2023062520401590400_c20","doi-asserted-by":"publisher","first-page":"1017","DOI":"10.1063\/1.1679283","volume":"58","year":"1973","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c21","doi-asserted-by":"publisher","first-page":"203","DOI":"10.1016\/0166-1280(85)80164-0","volume":"123","year":"1985","journal-title":"J. Mol. Struct.: THEOCHEM"},{"key":"2023062520401590400_c22","doi-asserted-by":"publisher","first-page":"7696","DOI":"10.1021\/ja00311a078","volume":"107","year":"1985","journal-title":"J. Am. Chem. Soc."},{"key":"2023062520401590400_c23","doi-asserted-by":"publisher","first-page":"329","DOI":"10.1063\/1.452622","volume":"86","year":"1987","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c24","doi-asserted-by":"publisher","first-page":"259","DOI":"10.1016\/0009-2614(80)87016-3","volume":"76","year":"1988","journal-title":"Chem. Phys. Lett."},{"key":"2023062520401590400_c25","doi-asserted-by":"publisher","first-page":"1775","DOI":"10.1063\/1.454101","volume":"88","year":"1988","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c26","doi-asserted-by":"crossref","DOI":"10.1007\/978-1-4684-7424-4","article-title":"The structure of small molecules and ions","volume-title":"Proc. Int. Workshop of Prof. Itzhak Plesser, Plesser, Neve llan, Israel, 13\u201318 December, 1987","author":"Naaman","year":"1988"},{"key":"2023062520401590400_c27","doi-asserted-by":"publisher","first-page":"219","DOI":"10.1016\/0301-0104(90)90020-A","volume":"146","year":"1990","journal-title":"Chem. Phys."},{"key":"2023062520401590400_c28","doi-asserted-by":"publisher","first-page":"6551","DOI":"10.1063\/1.461525","volume":"95","year":"1991","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c29","doi-asserted-by":"publisher","first-page":"154108","DOI":"10.1063\/1.3382912","volume":"132","year":"2010","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c30","doi-asserted-by":"publisher","first-page":"134","DOI":"10.1016\/j.cplett.2010.06.011","volume":"494","year":"2010","journal-title":"Chem. Phys. Lett."},{"key":"2023062520401590400_c31","doi-asserted-by":"publisher","first-page":"174304","DOI":"10.1063\/1.3658641","volume":"135","year":"2011","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c32","doi-asserted-by":"publisher","first-page":"034110","DOI":"10.1063\/1.3677273","volume":"136","year":"2012","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c33","first-page":"213","volume-title":"Advances in Molecular Structure Theory: Calculation and Characterization of Molecular Potential Energy Surfaces","author":"Dunning","year":"1990"},{"key":"2023062520401590400_c34","doi-asserted-by":"publisher","first-page":"3791","DOI":"10.1063\/1.1695818","volume":"42","year":"1965","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c35","doi-asserted-by":"publisher","first-page":"1171","DOI":"10.1063\/1.1696898","volume":"43","year":"1965","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c36","doi-asserted-by":"publisher","first-page":"2196","DOI":"10.1063\/1.1674313","volume":"53","year":"1970","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c37","doi-asserted-by":"publisher","first-page":"13","DOI":"10.1088\/0031-8949\/3\/1\/004","volume":"3","year":"1971","journal-title":"Phys. Scr."},{"key":"2023062520401590400_c38","doi-asserted-by":"publisher","first-page":"4256","DOI":"10.1063\/1.1674669","volume":"54","year":"1971","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c39","doi-asserted-by":"publisher","first-page":"165","DOI":"10.1098\/rspa.1972.0003","volume":"326","year":"1972","journal-title":"Proc. R. Soc. London, Ser. A"},{"key":"2023062520401590400_c40","doi-asserted-by":"publisher","first-page":"149","DOI":"10.1016\/0368-2048(80)85013-4","volume":"20","year":"1980","journal-title":"J. Electron Spectrosc. Relat. Phenom."},{"key":"2023062520401590400_c41","doi-asserted-by":"publisher","first-page":"3700","DOI":"10.1021\/ja00324a066","volume":"106","year":"1984","journal-title":"J. Am. Chem. Soc."},{"key":"2023062520401590400_c42","doi-asserted-by":"publisher","first-page":"674","DOI":"10.1063\/1.452268","volume":"86","year":"1987","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c43a","doi-asserted-by":"publisher","first-page":"2793","DOI":"10.1103\/PhysRevLett.57.2793","volume":"57","year":"1986","journal-title":"Phys. Rev. Lett."},{"key":"2023062520401590400_c43b","doi-asserted-by":"publisher","first-page":"98","DOI":"10.1016\/0168-583X(88)90521-6","volume":"33","year":"1988","journal-title":"Nucl. Instrum. Methods Phys. Res. B"},{"key":"2023062520401590400_c43c","doi-asserted-by":"crossref","DOI":"10.1007\/978-1-4684-7424-4","article-title":"The structure of small molecules and ions","volume-title":"Proceedings of International Workshop of Professor Itzhak Plesser","author":"Naaman","year":"1988"},{"key":"2023062520401590400_c44","doi-asserted-by":"publisher","first-page":"3377","DOI":"10.1063\/1.470222","volume":"103","year":"1995","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c45","doi-asserted-by":"publisher","first-page":"2309","DOI":"10.1063\/1.477965","volume":"110","year":"1999","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c46","doi-asserted-by":"publisher","first-page":"144305","DOI":"10.1063\/1.2712840","volume":"126","year":"2007","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c47","doi-asserted-by":"publisher","first-page":"245","DOI":"10.1126\/science.130.3370.245","volume":"130","year":"1959","journal-title":"Science"},{"key":"2023062520401590400_c48","doi-asserted-by":"publisher","first-page":"1810","DOI":"10.1021\/ja028820u","volume":"125","year":"2003","journal-title":"J. Am. Chem. Soc."},{"key":"2023062520401590400_c49","doi-asserted-by":"publisher","first-page":"147","DOI":"10.1098\/rspa.1975.0095","volume":"344","year":"1975","journal-title":"Proc. R. Soc. London, Ser. A"},{"key":"2023062520401590400_c50","year":"2002"},{"key":"2023062520401590400_c51","doi-asserted-by":"publisher","first-page":"73","DOI":"10.1016\/0009-2614(90)87014-I","volume":"165","year":"1990","journal-title":"Chem. Phys. Lett."},{"key":"2023062520401590400_c52","doi-asserted-by":"publisher","first-page":"3199","DOI":"10.1063\/1.463007","volume":"97","year":"1992","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c53","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1016\/S0370-1573(99)00047-2","volume":"324","year":"2000","journal-title":"Phys. Rep."},{"key":"2023062520401590400_c54","doi-asserted-by":"crossref","DOI":"10.1002\/9783527627400","volume-title":"Multidimensional Quantum Dynamics: MCTDH Theory and Applications","author":"Meyer","year":"2009"},{"key":"2023062520401590400_c55","volume-title":"Lanczos Algorithms for Large Symmetric Eigenvalue Problems","year":"1985"},{"key":"2023062520401590400_c56","doi-asserted-by":"crossref","first-page":"3166","DOI":"10.1002\/0470845015","volume-title":"Encyclopedia of Computational Chemistry","author":"Schleyer","year":"1998"},{"key":"2023062520401590400_c57","doi-asserted-by":"publisher","first-page":"5824","DOI":"10.1021\/ja00332a012","volume":"106","year":"1984","journal-title":"J. Am. Chem. Soc."},{"key":"2023062520401590400_c58a","doi-asserted-by":"publisher","first-page":"495","DOI":"10.1016\/0375-9601(73)90990-0","volume":"44","year":"1973","journal-title":"Phys. Lett. A"},{"key":"2023062520401590400_c58b","first-page":"1023","volume":"39","year":"1974","journal-title":"Sov. Phys. JETP"},{"key":"2023062520401590400_c59","doi-asserted-by":"publisher","first-page":"1002","DOI":"10.1103\/PhysRev.73.1002","volume":"73","year":"1948","journal-title":"Phys. Rev."},{"key":"2023062520401590400_c60","doi-asserted-by":"publisher","first-page":"851","DOI":"10.1080\/00268978100101721","volume":"43","year":"1981","journal-title":"Mol. Phys."},{"key":"2023062520401590400_c61","doi-asserted-by":"publisher","first-page":"1007","DOI":"10.1063\/1.456153","volume":"90","year":"1989","journal-title":"J. Chem. Phys."},{"key":"2023062520401590400_c62","year":"2003"},{"key":"2023062520401590400_c63"},{"key":"2023062520401590400_c64","doi-asserted-by":"publisher","first-page":"213","DOI":"10.1016\/0022-2852(79)90103-6","volume":"77","year":"1979","journal-title":"J. Mol. Spectsc."},{"key":"2023062520401590400_c65"},{"key":"2023062520401590400_c66a","doi-asserted-by":"crossref","first-page":"164","DOI":"10.1090\/qam\/10666","volume":"2","year":"1944","journal-title":"Q. Appl. Math."},{"key":"2023062520401590400_c66b","doi-asserted-by":"publisher","first-page":"431","DOI":"10.1137\/0111030","volume":"11","year":"1963","journal-title":"SIAM J. Appl. Math."}],"container-title":["The Journal of Chemical Physics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pubs.aip.org\/aip\/jcp\/article-pdf\/doi\/10.1063\/1.4768675\/15458493\/214320_1_online.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/pubs.aip.org\/aip\/jcp\/article-pdf\/doi\/10.1063\/1.4768675\/15458493\/214320_1_online.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,5,3]],"date-time":"2024-05-03T01:20:03Z","timestamp":1714699203000},"score":1,"resource":{"primary":{"URL":"https:\/\/pubs.aip.org\/jcp\/article\/137\/21\/214320\/192252\/Quadratic-coupling-treatment-of-the-Jahn-Teller"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2012,12,7]]},"references-count":77,"journal-issue":{"issue":"21","published-print":{"date-parts":[[2012,12,7]]}},"URL":"https:\/\/doi.org\/10.1063\/1.4768675","relation":{},"ISSN":["0021-9606","1089-7690"],"issn-type":[{"value":"0021-9606","type":"print"},{"value":"1089-7690","type":"electronic"}],"subject":[],"published-other":{"date-parts":[[2012,12,7]]},"published":{"date-parts":[[2012,12,7]]},"article-number":"214320"}}