Molecular States

  • Maurizio Persico
  • Giovanni Granucci
Part of the Theoretical Chemistry and Computational Modelling book series (TCCM)


This chapter will introduce the quantum mechanical equation of motion, i.e., the time-dependent Schrödinger equation. We will show how the separation of variables can be exploited to partition the molecular wavefunction in translational, rotational, vibrational, and electronic components, with special emphasis on the Born–Oppenheimer approximation and its breakdown. We shall then provide an overview of the electronic structure and reactivity of excited states commonly found in organic molecules.


Molecular states Born Oppenheimer approximation Electric excited states Photochemical reactions 


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Chemistry and Industrial ChemistryUniversity of PisaPisaItaly

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