# Photoinduced Spin Polarization of a Gadolinium Complex

## TL;DR

This paper shows how light can change the magnetic properties of a gadolinium complex through a neighboring organic molecule.

## Contribution

A new method to manipulate lanthanide ion polarization via photoexcitation of a chromophore is proposed.

## Key findings

- Photoexcitation of an organic chromophore alters the spin polarization of a gadolinium(III) ion.
- The EPR signal of the lanthanide ion inverts due to this photochemical interaction.
- The mechanism is elucidated using a combination of spectroscopic and theoretical methods.

## Abstract

This paper explores
the interaction between a photoexcited organic
chromophore and a gadolinium­(III) ion in a complex, which exhibits
an intriguing time evolution of the spin polarization in its electron
paramagnetic resonance (EPR) signature. Time-resolved EPR, transient
absorption, and photoluminescence spectroscopies combine with results
from density functional theory and spectral simulations to allow elucidation
of the photochemical mechanism and its impact on the complex’s
magnetic properties. We show that perturbation of the polarization
of a gadolinium­(III) ion is possible via photoexcitation of a neighboring,
organic chromophore, reflected in the inversion of the lanthanide
ion’s EPR signal. We, therefore, suggest a new avenue to initialize
and manipulate lanthanide-based qudits with potential applications
in quantum information science.