Photochemistry in Real Space: Batho‐ and Hypsochromism in the Water Dimer

Abstract

AbstractThe development of chemical intuition in photochemistry faces several difficulties that result from the inadequacy of the one‐particle picture, the Born–Oppenheimer approximation, and other basic ideas used to build models. It is shown herein how real‐space approaches can be efficiently used to gain valuable insights in photochemistry through a simple example of red and blue shift effects: the double hypso‐ and bathochromic shifts in the low‐lying valence excited states of (H2O)2. It is demonstrated that 1) the use of these techniques allows the perturbative language used in the theory of intermolecular interactions, even in the strongly interacting short‐range regime, to be maintained; 2) one and only one molecule is photoexcited in each of the addressed excited states and 3) the electrostatic interaction between the in‐the‐cluster molecular dipoles provides a fairly intuitive rationalisation of the observed batho‐ and hypsochromism. The methods exploited and illustrated herei

Aurora Costales Castro

Associate Professor

Associate Professor of Physical Chemistry at the University of Oviedo. Her research applies quantum chemical topology to study chemical bonding in solids, clusters, and molecular systems.

Evelio Francisco Miguélez

Associate Professor

Associate Professor of Physical Chemistry at the University of Oviedo. Expert in the development and application of quantum chemical topology methods, IQA analysis, and electron correlation descriptors.