Non-Kasha fluorescence

Kasha’s rule states that fluorescence generally occurs from the lowest excited singlet state (S1). Exceptions to this rule are usually associated with a metastable S2 state that is separated from S1 not allowing for interconversion. In a recent article we outlined a different mechanism for non-Kasha fluorescence: If S1 and S2 are very close in energy, then S2 is populated in a dynamic equilibrium following Boltzmann statistics. This effect is particularly pronounced if there is a large amount of vibrational excess energy following excitation into a high-energy absorption peak. The full story, “Non-Kasha fluorescence of pyrene emerges from a dynamic equilibrium between excited states” was just published in J. Chem. Phys.

Eu(III) complexes

Our new paper “Impact of Varying the Phenylboronic Acid Position in Macrocyclic Eu(III) Complexes on the Recognition of Adenosine Monophosphate“, led by S. E. Bodman and S. J. Butler from Loughborough, just appeared in Organic Chemistry Frontiers. The paper is the second in a series studying the anion sensing properties of Eu(III) complexes with phenylboronic acids.

Aside from reporting the synthesis and anion binding, the paper presents new strategies for the computational analysis of such complexes. Aside from modelling the geometries by density functional theory, high-level multireference methods in OpenMolcas were applied to study the luminescence properties. These first principles computations offer a promising approach to access the emission spectra of lanthanide complexes, aiding the design of responsive lanthanide probes with specific photophysical properties

Release of TheoDORE 3.0

Version 3.0 of the TheoDORE wavefunction analysis package is available. Download the current version below.

New features of TheoDORE 3.0

  • New user interface and documentation
  • Improvement for VIST (plot_vist)
  • Improvements for natural orbital analysis (analyze_nos) including unrestricted orbitals
  • LOC for ionic states (analyze_tden)
  • Jmol densities (jmol_mos)
  • State-to-state TDM
  • Updated ADF interface
  • ONETEP interface
  • Excitation number, modified from [DOI: (10.1021/acs.jctc.7b00963)]

Note: TheoDORE 3 has a modified user interface. To use TheoDORE call

theodore theoinp

theodore analyze_tden

theodore analyze_nos


TheoDORE – Download

Download the newest release of the TheoDORE wavefunction analysis program – TheoDORE 3.1.1 (23 June 2023)

Size: 12 MB
Version: 3.1.1

Full release notes

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Substituted macrocycles

A recent study, lead by Florian Glöcklhofer from Imperial College London, explores the effect of methoxy and thiomethyl subtitutions on a formally antiaromatic macrocycle. The corresponding paper “[]Paracyclophanetetraenes (PCTs): cyclic structural analogues of poly(p‑phenylene vinylene)s (PPVs)” is available via Open Research Europe, 1, 111, 2012.

The above figure compares the orbitals and aromaticity descriptors for different charge and spin states. Importantly, the symmetry is broken in the T1 state, inhibiting Baird aromaticity. By comparison, the symmetry is retained for the neutral singlet, dianion, and dication states all of which exhibit aromaticity.