Two-photon absorption cross-sections of reference dyes: a critical examination

Area of Science:

• Computational Chemistry
• Photophysics
• Spectroscopy

Background:

• Fluorophores such as p-bis(o-methoxystyryl)benzene (Bis-MSB), coumarin 307, fluorescein, and rhodamine B are widely used as reference compounds.
• Existing literature reports significant discrepancies in measured two-photon absorption cross-sections for these compounds.

Purpose of the Study:

• To theoretically calculate and compare the electronic structure and one- and two-photon absorption spectra of four common fluorophores.
• To investigate the reasons behind the discrepancies in reported two-photon absorption cross-sections.
• To study the influence of solvent environments on spectral properties.

Main Methods:

• Theoretical calculations of electronic structure and absorption spectra.
• Comparison of theoretical results with available experimental data.
• Analysis of solvent effects on spectral properties.

Main Results:

• Theoretical calculations provide insights into the electronic structure and spectral properties of the studied fluorophores.
• The study identifies potential reasons for the wide variations in literature values for two-photon absorption cross-sections.
• The impact of solvent environments on one- and two-photon absorption spectra has been elucidated.

Conclusions:

• Theoretical findings help explain discrepancies in two-photon absorption cross-section data.
• Solvent effects play a significant role in the observed spectral characteristics.
• Precautions are necessary when comparing two-photon absorption cross-section data from different literature sources.