Related Experiment Video
Updated: May 18, 2026
08:46
Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
Published on: November 22, 2016
P=P bond photophysics in an Ar-P=P-Ar diphosphene
Huo-Lei Peng1, John L Payton, John D Protasiewicz
1Department of Chemistry, Case Western Reserve University, Cleveland, OH, USA.
Dalton Transactions (Cambridge, England : 2003)
|September 28, 2012
Summary
The photophysics of diphosphene DmpP=PDmp were studied using spectroscopy and computation. Excited states S(1) and S(2) decay rapidly on sub-nanosecond timescales with no observed irreversible photochemistry.
Area of Science:
- Photochemistry and photophysics
- Organophosphorus chemistry
- Computational chemistry
Background:
- Diphosphenes are compounds containing a phosphorus-phosphorus double bond.
- Understanding their excited-state dynamics is crucial for predicting reactivity and potential applications.
- Previous studies on related compounds suggest complex photophysical pathways.
Purpose of the Study:
- To investigate the excited-state photophysics of diphosphene DmpP=PDmp.
- To determine the lifetimes and spectral characteristics of the S(1) and S(2) excited states.
- To elucidate the decay mechanisms and potential photochemical pathways.
Main Methods:
- Femtosecond transient absorption spectroscopy with 480 nm and 400 nm excitation.
- Computational modeling using CASSCF and CASPT2 levels of theory.
- Analysis of spectral features and decay kinetics.
Main Results:
- The S(2) excited state has a lifetime of 275 fs with an absorption feature at the red end of the visible spectrum.
- The S(1) state does not absorb significantly in the probe range.
- Excited states decay biexponentially on sub-nanosecond timescales (~20 ps and a few hundred ps) via phenyl torsional motions and intersystem crossing.
Conclusions:
- Diphosphene DmpP=PDmp exhibits rapid excited-state decay on sub-nanosecond timescales.
- No irreversible photochemistry was observed.
- Computational and experimental data support a model involving phenyl torsional twisting and intersystem crossing to triplet states.
![[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
Related Concept Videos
03:35Hybridization of Atomic Orbitals II
sp3d and sp3d 2 Hybridization
02:35Molecular Orbital Theory I
Overview of Molecular Orbital Theory
01:24π Molecular Orbitals of 1,3-Butadiene
Conjugated dienes have lower heats of hydrogenation than cumulated and isolated dienes, making them more stable. The enhanced stabilization of conjugated systems can be understood from their π molecular orbitals.
The simplest conjugated diene is 1,3-butadiene: a four-carbon system where each carbon is sp2-hybridized and has an unhybridized p orbital that contains an unpaired electron. According to molecular orbital theory, atomic orbitals combine to form molecular orbitals such that the number...
The simplest conjugated diene is 1,3-butadiene: a four-carbon system where each carbon is sp2-hybridized and has an unhybridized p orbital that contains an unpaired electron. According to molecular orbital theory, atomic orbitals combine to form molecular orbitals such that the number...
03:24Hybridization of Atomic Orbitals I
The mathematical expression known as the wave function, ψ, contains information about each orbital and the wavelike properties of electrons in an isolated atom. When atoms are bound together in a molecule, the wave functions combine to produce new mathematical descriptions that have different shapes. This process of combining the wave functions for atomic orbitals is called hybridization and is mathematically accomplished by the linear combination of atomic orbitals. The new orbitals that...
02:36Molecular Geometry and Dipole Moments
The VSEPR theory can be used to determine the electron pair geometries and molecular structures as follows:
02:40MO Theory and Covalent Bonding
The molecular orbital theory describes the distribution of electrons in molecules in a manner similar to the distribution of electrons in atomic orbitals. The region of space in which a valence electron in a molecule is likely to be found is called a molecular orbital. Mathematically, the linear combination of atomic orbitals (LCAO) generates molecular orbitals. Combinations of in-phase atomic orbital wave functions result in regions with a high probability of electron density, while...