Structural Investigations of Vapochromic Behavior. X-ray Single-Crystal and Powder Diffraction Studies of [Pt(CN-iso-C₃H₇)₄][M(CN)₄] for M = Pt or Pd

Abstract

We have synthesized [Pt(CN-iso-C 3 H 7 ) 4 ][M(CN) 4 ] (M ) Pt, Pd) and studied their reversible hydration and sorption properties with UV-vis, FT-IR spectroscopy, and X-ray diffraction. Powder diffraction studies show that anhydrous [Pt(CN-iso-C 3 H 7 ) 4 ][Pt(CN) 4 ] and [Pt(CN-iso-C 3 H 7 ) 4 ][Pd(CN) 4 ] crystallize in a tetragonal space group with nearly identical lattice constants. Gravimetric studies reveal that variable guest-host stoichiometries occur when solid [Pt(CN-iso-C 3 H 7 ) 4 ][Pt(CN) 4 ] sorbs the guest at room temperature from the gas phase [water, 12.1(1) molecules per formula unit, chloroform 6.0(1), methanol 8.0(1), and trifluoroethanol 4.1(1)]; these sorption processes are reversible. The unit cell distances in the tetragonal ab-plane expand dramatically when the solvent guests are sorbed, but changes along the c-axis (the M-M direction) are minimal. Crystallization of [Pt(CN-iso-C 3 H 7 ) 4 ][Pt(CN) 4 ] from water gives monoclinic crystals of a hexadecahydrate [Pt(CN-iso-C 3 H 7 ) 4 ][Pt(CN) 4 ]‚16H 2 O. This salt consists of alternating cation/anion chains along b with an average Pt-Pt distance of b/2 ) 3.1521(1) Å. The sixteen water molecules per formula weight interlace neighboring chains via H-bonding with each other and the CNions of the Pt(CN) 4 2units. The shifts in the UV-vis and IR spectra that occur when solvent guests are sorbed by the double complex salts are discussed in terms of the lattice expansions that are observed. A mechanism for the lattice expansions that accompany the sorption of guest molecules is proposed.

Electronic Structures and Spectroscopic Properties of [Pt(CNMe)2(CN)2]n (n = 1–4): A Theoretical Exploration of Promising Phosphorescent Materials

“…The optimized S 0 structures of the platinum(II) monomer and dimer, with the coordination axis, are depicted in Figure 1, and the corresponding important parameters are listed in Table 1. As shown in Table 1, the geometrical parameters for the monomer and dimer are very close and agree well with most of the experimental values for [Pt(CN) 4 2-] ions and for double salts such as [Pt(CNR) 4 (CN) 4 ] (R = toluene), [14] which indicates that the eclipsed structures do not have an impact on the geometrical structure of the monomer. The Pt-C1 and C1ϵN1 bonds are ca.…”

“…In fact, similar neutral platinum(II) complexes with the general formulas [Pt(CNR) 4 ][Pt(CN) 4 ] and [Pt(CNR) 2 (CN) 2 ] 2 (R = alkyl and aryl) have been extensively studied by Mann and coworkers. [14] However, their investigation was limited to their application towards chemical sensors and their vapochromic behavior, and there was little discussion on their luminescence properties and the effect of oligomerization on the luminescence and the electronic structures. Furthermore, to the best of our knowledge, the luminescent properties for oligomerized [Pt(CNtBu) 2 (CN) 2 ] n have not been theoretically investigated for the platinum(II) complexes.…”

Polymer‐Induced Self‐Assembly of Alkynylplatinum(II) Terpyridyl Complexes by Metal⋅⋅⋅Metal/π⋅⋅⋅π Interactions

“…[2][3][4][5][6][7][8][9] These complexes are known to display a strong tendency towards the formation of highly ordered extended linear chains or oligomeric structures in the solid state. [1e, 2, 4, 5a] A particularly interesting class of platinum(ii) complexes is the polypyridyl complexes.…”

Detection of Volatile Organic Compounds Based on Optical Fibre using Nanostructured Films

“…Although there is a great number of complexes showing solvatochromism (change in absorbance properties when dissolved in different liquids), for the construction of VOCs sensors, it is more important other property, the vapochromism. This term was present firstly by Nagel and Mann and co-workers [9] to describe complexes that change the colour in presence of VOCs.…”