Vibrational Signature of Metallophilic Interactions in [Pt(terpy)Cl][Au(CN)₂]

Abstract

Metallophilic interactions, weak interactions between closed-shell metal atoms, have been recently utilized to create unique nanostructures with anisotropy of electronic properties along the direction of the interaction. The strength of the metallophilic interaction is an important factor for the design of these nanostructures. Recently, Doerrer and co-workers presented a general metathesis route to create extended chains of metallophilic double salts with two modular opposite-charge ions with Au­(I) and Pt­(II) centers without bridging ligands. Here, we apply theoretical and experimental angle-resolved Raman spectroscopy to identify the vibrational signature associated with the Au­(I)–Pt­(II) interaction in the double salt wire, [Pt­(terpy)­Cl]­[Au­(CN)2)]. Our study reveals six Raman-active low-energy phonon modes below 75 cm–1 that are anisotropic, as shown by their polarization dependence. By analysis of the low-energy Raman spectrum and the nature of the associated phonon modes, we identify one mode to be associated with the intrachain Pt–Au interactions with a frequency of 57 cm–1. We show that the polarization dependence of the Raman spectrum is the key to elucidating directional metallophilic modes.

Ratiometric and Colorimetric Optical Thermometers Using Emissive Dimeric and Trimeric {[Au(SCN)2]−}n Moieties Generated in d–f Heterometallic Assemblies

“…Raman measurements in the 4 000–100 cm −1 range contain several peaks that originate from the organic ligand and cyanide stretching frequency, similar to those in the IR spectrum. However, several other reports have shown that two gold atoms are in close proximity and show the so‐called Au⋅⋅⋅Au stretching frequency located below 200 cm −1 [7b, 14] …”

Slow magnetic relaxation in Nd(iii) and Sm(iii) complexes formed in three-dimensional lanthanide-dicyanidometallate(i) frameworks exhibiting luminescent properties

“…Previously, we discovered that the photon density of the triplet emission decreases upon cooling and it is closely related to the Au⋯Au vibrations (110 cm −1 ). 55,68…”

“…Previously, we discovered that the photon density of the triplet emission decreases upon cooling and it is closely related to the AuÁ Á ÁAu vibrations (110 cm À1 ). 55,68 To ascertain the thermosensitivity and usability of the thermal sensor, we evaluated the relative thermal sensitivity (S r ) by taking the first derivative of the fitted thermometric parameter D(T) calibration curve as a function of temperature: S r = (qD/qT)/D (Table S23, ESI †). S r was calculated for both thermometric parameters and two excitation energies concerning the temperature given in Fig.…”

Experimental assignment of long-range magnetic communication through Pd & Pt metallophilic contacts

“…The computed potential energy surfaces demonstrating reasonable stabilization and concomitant curvature around the minima raises the question of whether the M′⋯M′ stretching may actually be experimentally observable. Very recently 43 the vibrational signature of the Au–Pt metallophilic interaction in [Pt(terpy)Cl][Au(CN) 2 ] was observed experimentally at 57 cm −1 . This system is well selected for this specific purpose due to the rigidity and the scarcity of obvious low-energy modes.…”