# Oxovanadium(IV) Thiocarboxylate Paddlewheels Containing Ancillary Group 10 Metals: A Comparative Study on Pd and Pt Derivatives

## TL;DR

This paper compares vanadium-based molecular structures with palladium and platinum, focusing on their magnetic and quantum properties.

## Contribution

The study introduces Pd derivatives of vanadyl thiocarboxylate paddlewheels and compares them to Pt analogs.

## Key findings

- Pd complexes show stronger antiferromagnetic coupling than Pt complexes in staggered dimers.
- Pd derivatives undergo more favorable one-electron reduction in solution compared to Pt.
- Quantum coherence times remain unchanged between Pd and Pt derivatives despite differences in redox and magnetic properties.

## Abstract

Vanadyl-containing paddlewheel structures have recently
joined
the pool of molecular spin systems showing respectable coherence times
(T
m). We extended the investigation of
[PtVO­(SOCR)4] (R = Me, Ph) by synthesizing the corresponding
Pd derivatives. Crystals of [PdVO­(SOCMe)4] and [PdVO­(SOCPh)4]·DCM are isomorphous to their Pt analogues and comprise
staggered and square dimers, respectively. For both Group 10 metals,
M···M′ contacts in staggered dimers promote
a stronger antiferromagnetic coupling than M···S′
contacts in square dimers, with Pd complexes showing a slightly more
effective interaction consistent with DFT predictions. In solution,
the paddlewheels exist in monomeric form and undergo a quasi-reversible
one-electron reduction, more favorable for M = Pd than Pt and for
R = Ph than Me. X-band EPR spectra in frozen CD2Cl2/toluene-d
8 show the eight-line
hyperfine pattern characteristic of 51V (I = 7/2), with identical spin-Hamiltonian parameters across the series.
Unlike the interaction with 195Pt (I =
1/2, 34%), the superhyperfine coupling with 105Pd (I = 5/2, 22%) is unresolved. T
m values are essentially the same for Pt and Pd derivatives and follow
the same substituent dependence (Ph > Me). Therefore, the ancillary
Group 10 metal affects redox potentials and, to a lesser extent, solid-state
magnetic properties, but leaves quantum coherence unchanged.