# Coordination of XeF2 to Fluoridometal Cations: The Adduct Cations [PtF3(XeF2)3]+ and [PdF3(XeF2)3]+

## TL;DR

This paper reports the discovery of new cations where xenon difluoride coordinates with palladium and platinum, expanding noble-gas coordination chemistry.

## Contribution

The study identifies and characterizes new cations [PtF3(XeF2)3]+ and [PdF3(XeF2)3]+, the first examples of XeF2 ligating to a fluoridometal cation.

## Key findings

- The [MF3(XeF2)3]+ cations are mononuclear and cationic, with multiple XeF2 ligands bound to a single metal center.
- Quantum-chemical calculations align well with the experimental crystal structures of the adduct cations.
- These cations represent a new class of XeF2 coordination compounds, expanding noble-gas coordination chemistry.

## Abstract

Crystals of the double
salts [Xe2F3]­[MF3(XeF2)3]­[AsF6]2 (M = Pd, Pt), prepared
from anhydrous HF solutions, were characterized
by low-temperature single-crystal X-ray diffraction and Raman spectroscopy.
The crystal structures reveal that the compounds contain the hitherto
unobserved [MF3(XeF2)3]+ adduct cations, which differ from all previously identified examples
of XeF2 coordination to a metal­(IV) center in their mononuclear
and cationic nature, as well as in the coordination of multiple XeF2 ligands to a single metal­(IV) center. Quantum-chemical calculations
were performed to gain insight into the bonding and electronic structure
of the [MF3(XeF2)3]+ adduct
cations, with the optimized gas-phase geometries showing good agreement
with the experimental solid-state structures. The characterized [MF3(XeF2)3]+ adduct cations
markedly extend the chemistry of XeF2–MF4 systems and represent rare, crystallographically characterized examples
of XeF2 coordination to PtIV and PdIV, a feature also believed to occur in the structure of the first
discovered noble-gas compound, XePtF6. Moreover, the [MF3(XeF2)3]+ cations constitute
the first examples of a new class of XeF2 coordination
compounds, which are characterized by XeF2 ligation to
a fluoridometal [MF

x

]
n+ cation, thereby enabling further expansion
of the coordination chemistry of noble-gas fluorides.