Cracking down on vapochromic salts: unveiling vapomechanical stress in gas-sorbing platinum complexes.

This study explores the vapochromic and vapoluminescent behaviors of [Pt(tpy)Cl]PF host molecules (tpy = 2,2':6',2''-terpyridine) under acetonitrile (CHCN) vapor guest, challenging the conventional view that these phenomena arise solely from direct host-guest interactions. Our findings reveal a cooperative mechanism where mechanochromic surface perturbations prime the Pt(II) host for guest incorporation, leading to initial color and luminescence changes prior to significant structural alterations. While the color transition between the yellow [Pt(tpy)Cl]PF form and the red/orange [Pt(tpy)Cl]PF·CHCN form is reversible, repeated vapor cycling induces a loss of crystallinity, as indicated by diffraction peak broadening and emission shifts.

Optical sensing of aqueous nitrate anion by a platinum(II) triimine salt based solid state material.

Selective and quantitative measurement of aqueous nitrate (NO) anion is achieved using solid [Pt(Cl-4-tpy)Cl]ClO salt (Cl-4-tpy = 4-chloro-2,2':6'2''-terpyridine), and as the salt supported on controlled porous glass. This detection method relies on the color change of the Pt(II) complex from yellow to red and intense luminescence response upon ClO exchange with NO due to concomitant enhancement of Pt⋯Pt interactions. The spectroscopic response is highly selective for NO over a large range of halides and oxoanions.

Water's Role in Polymorphic Platinum(II) Complexes.

Solvent plays a vital role in the recrystallization process and resulting crystallinity of materials. This role is of such importance that it can control the stability and utility of materials. In this work, the inclusion of a solvent in the crystalline lattice, specifically water, drastically affects the overall stability of two platinum polymorphs.

pH-Mediated Colorimetric and Luminescent Sensing of Aqueous Nitrate Anions by a Platinum(II) Luminophore@Mesoporous Silica Composite.

Increased levels of nitrate (NO) in the environment can be detrimental to human health. Herein, we report a robust, cost-effective, and scalable, hybrid material-based colorimetric/luminescent sensor technology for rapid, selective, sensitive, and interference-free NO detection. These hybrid materials are based on a square-planar platinum(II) salt [Pt(tpy)Cl]PF (tpy = 2,2';6',2″-terpyridine) supported on mesoporous silica.

Phase transformation induced mechanochromism in a platinum salt: a tale of two polymorphs.

Red crystals of [Pt(tpy)Cl]NO3·HNO3 show mechanochromic behaviour turning yellow when pressure is applied. The electronic character and spectroscopic signature of the red and yellow polymorphs change as a result of slipping of the molecular stacking planes in the solid state. The slippage alters the PtPt intermolecular distances from a linear stacked motif with <3.