Тип публикации: статья из журнала
Год издания: 2024
Идентификатор DOI: 10.1103/physreva.110.033119
Аннотация: <jats:p>Photodissociation is one of the most important photoinduced chemical reactions. It occurs when the potential energy curve along a chemical bond is repulsive in an excited state. Typically, “ballistic” ultrafast dissociation leads to the broadening of absorption resonances and the smearing out of vibrational fine-structure. Показать полностьюWe report on the photodissociation of <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:msub><a:mi mathvariant="normal">H</a:mi><a:mn>2</a:mn></a:msub><a:mi mathvariant="normal">O</a:mi></a:mrow></a:math> in the <d:math xmlns:d="http://www.w3.org/1998/Math/MathML"><d:mover accent="true"><d:mi>B</d:mi><d:mo>̃</d:mo></d:mover><d:mo> </d:mo><d:mrow><d:mn>2</d:mn><d:mspace width="0.16em"/><d:mmultiscripts><d:mi>A</d:mi><d:mn>1</d:mn><d:none/><d:mprescripts/><d:none/><d:mn>1</d:mn></d:mmultiscripts></d:mrow></d:math> electronic state, characterized by a <g:math xmlns:g="http://www.w3.org/1998/Math/MathML"><g:mrow><g:mrow><g:mo>|</g:mo><g:mn>3</g:mn></g:mrow><g:msubsup><g:mi>a</g:mi><g:mn>1</g:mn><g:mrow><g:mo>−</g:mo><g:mn>1</g:mn></g:mrow></g:msubsup><g:mn>4</g:mn><g:msubsup><g:mi>a</g:mi><g:mn>1</g:mn><g:mn>1</g:mn></g:msubsup><g:mrow><g:mo>〉</g:mo></g:mrow></g:mrow></g:math> configuration, which can be reached via resonant inelastic x-ray scattering or direct ultraviolet absorption. In both cases the spectra show narrow vibrational resonances, in spite of the dissociative character of the state. We find that “delayed” dissociation pathways, caused by reflection of the nuclear wave packet, are responsible for this effect. In spite of the analogous topology of the potential energy surfaces of the core- and valence-excited states, the reflection of the wave packet takes place only in the latter. The two-dimensional wave packet of the O-H stretching coordinates becomes trapped in a “cavity” near the Franck-Condon region, resulting from a mismatch between the OH vibrational frequency in the cavity and the one at the dissociation limit.</jats:p> <jats:sec> <jats:title/> <jats:supplementary-material> <jats:permissions> <jats:copyright-statement>Published by the American Physical Society</jats:copyright-statement> <jats:copyright-year>2024</jats:copyright-year> </jats:permissions> </jats:supplementary-material> </jats:sec>
Журнал: Physical Review A
Выпуск журнала: Т. 110, № 3
Номера страниц: 033119
ISSN журнала: 24699926
Издатель: American Physical Society