Polymer Thin Films as Universal Substrates for Extreme Ultraviolet Absorption Spectroscopy of Molecular Transition Metal Complexes

TL;DR

This study demonstrates that polystyrene and polyvinyl chloride thin films serve as effective, versatile, and high-transmission substrates for extreme ultraviolet spectroscopy of transition metal complexes, enabling new spectroscopic applications.

Contribution

It introduces the use of polymer thin films as universal, high-transmission supports for XUV spectroscopy of molecular transition metal complexes, including transient absorption studies.

Findings

Polymer films transmit more XUV light than silicon nitride.

Transition metal complexes' M-edge XANES spectra are successfully obtained.

Polymer films support pump/probe transient absorption spectroscopy.

Abstract

Polystyrene and polyvinyl chloride thin films are explored as sample supports for extreme ultraviolet (XUV) spectroscopy of molecular transition metal complexes. Thin polymer films prepared by slip-coating are flat, smooth, and transmit much more XUV light than silicon nitride windows. Analytes can be directly cast onto the polymer surface, or codeposited within it. The M-edge x-ray absorption near-edge (XANES) spectra (40-90 eV) of eight archetypal transition metal complexes (M=Mn, Fe, Co, Ni) are presented to demonstrate the versatility of this method. The films are suitable for pump/probe transient absorption spectroscopy, as shown by the excited-state spectra of Fe(bpy)$_3^{2+}$ in two different polymer supports.