Related Experiment Video
Updated: Aug 23, 2026

Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
Ground and excited states of NH4: Electron propagator and quantum defect analysis
J V Ortiz1, I Martin, A M Velasco
1Department of Chemistry, Kansas State University, Manhattan, Kansas 66506-3701, USA. ortiz@ksu.edu
Abstract:
Vertical excitation energies of the Rydberg radical NH4 are inferred from ab initio electron propagator calculations on the electron affinities of NH4+. The adiabatic ionization energy of NH4 is evaluated with coupled-cluster calculations. These predictions provide optimal parameters for the molecular-adapted quantum defect orbital method, which is used to determine Einstein emission coefficients and radiative lifetimes. Comparisons with spectroscopic data and previous calculations are discussed.
Related Concept Videos
Imperfections in Crystal Structure: Stoichiometric Point Defects
The Bohr Model
The de Broglie Wavelength
The Quantum-Mechanical Model of an Atom
Nuclear Overhauser Enhancement (NOE)
Nuclear Binding Energy

