16 research outputs found
Thermal Expansion Behavior of M<sup>I</sup>[AuX<sub>2</sub>(CN)<sub>2</sub>]āBased Coordination Polymers (M = Ag, Cu; X = CN, Cl, Br)
Two sets of <i>trans-</i>[AuX<sub>2</sub>(CN)<sub>2</sub>]<sup>ā</sup>-based coordination polymer materialsīøMĀ[AuX<sub>2</sub>(CN)<sub>2</sub>] (M = Ag; X = Cl, Br or M = Cu; X = Br) and MĀ[AuĀ(CN)<sub>4</sub>] (M = Ag, Cu)īøwere synthesized and structurally characterized
and their dielectric constants and thermal expansion behavior explored.
The MĀ[AuX<sub>2</sub>(CN)<sub>2</sub>] series crystallized in a tightly
packed, mineral-like structure featuring 1-D <i>trans-</i>[AuX<sub>2</sub>(CN)<sub>2</sub>]<sup>ā</sup>-bridged chains
interconnected via a series of intermolecular AuĀ·Ā·Ā·X
and MĀ·Ā·Ā·X (M = Ag, Cu) interactions. The MĀ[AuĀ(CN)<sub>4</sub>] series adopted a 2-fold interpenetrated 3-D cyano-bound
framework lacking any weak intermolecular interactions. Despite the
tight packing and the presence of intermolecular interactions, these
materials exhibited decreased thermal stability over unbound <i>trans-</i>[AuX<sub>2</sub>(CN)<sub>2</sub>]<sup>ā</sup> in [<sup><i>n</i></sup>Bu<sub>4</sub>N]Ā[AuX<sub>2</sub>(CN)<sub>2</sub>]. A significant dielectric constant of up to Īµ<sub>r</sub> = 36 for AgĀ[AuCl<sub>2</sub>(CN)<sub>2</sub>] (1 kHz) and
a lower Īµ<sub>r</sub> = 9.6 (1 kHz) for AgĀ[AuĀ(CN)<sub>4</sub>] were measured and interpreted in terms of their structures and
composition. A systematic analysis of the thermal expansion properties
of the MĀ[AuX<sub>2</sub>(CN)<sub>2</sub>] series revealed a negative
thermal expansion (NTE) component along the cyano-bridged chains with
a thermal expansion coefficient (Ī±<sub>CN</sub>) of ā13.7(11),
ā14.3(5), and ā11.36(18) ppmĀ·K<sup>ā1</sup> for AgĀ[AuCl<sub>2</sub>(CN)<sub>2</sub>], AgĀ[AuBr<sub>2</sub>(CN)<sub>2</sub>], and CuĀ[AuBr<sub>2</sub>(CN)<sub>2</sub>], respectively.
The AuĀ·Ā·Ā·X and AgĀ·Ā·Ā·X interactions affect
the thermal expansion similarly to metallophilic AuĀ·Ā·Ā·Au
interactions in MĀ[AuĀ(CN)<sub>2</sub>] and AuCN; replacing X = Cl with
the larger Br atoms has a less significant effect. A similar analysis
for the MĀ[AuĀ(CN)<sub>4</sub>] series (where the volume thermal expansion
coefficient, Ī±<sub>V</sub>, is 41(3) and 68.7(19) ppmĀ·K<sup>ā1</sup> for M = Ag, Cu, respectively) underscored the significance
of the effect of the atomic radius on the flexibility of the framework
and, thus, the thermal expansion properties
Raman Detected Sensing of Volatile Organic Compounds by Vapochromic Cu[AuX<sub>2</sub>(CN)<sub>2</sub>]<sub>2</sub> (X = Cl, Br) Coordination Polymer Materials
Two
vapochromic coordination polymers CuĀ[AuX<sub>2</sub>(CN)<sub>2</sub>]<sub>2</sub> (X = Cl, <b>1</b>; X = Br, <b>2</b>) were
prepared and spectroscopically characterized. Exposure of
these solid materials to the volatile organic compounds dimethylformamide
(DMF), dimethyl sulfoxide (DMSO), pyridine, 1,4-dioxane, and ethylene
glycol (glycol) resulted in distinct color, and IR and Raman changes.
The thermal stability of the analyte-bound materials was assessed
by thermogravimetric analysis. Single-crystal structures of CuĀ(analyte)<sub>4</sub>[AuX<sub>2</sub>(CN)<sub>2</sub>]<sub>2</sub> (analyte = DMF,
DMSO; X = Cl, Br) revealed an isostructural set of 1-D coordination
polymer chains, where the analyte molecules were equatorially O-bound
to the CuĀ(II) centers while axially bound [AuX<sub>2</sub>(CN)<sub>2</sub>]<sup>ā</sup> units bridged these CuĀ(II) centers, while
CuĀ(glycol)<sub>4</sub>[AuBr<sub>2</sub>(CN)<sub>2</sub>]<sub>2</sub> is molecular, with monodentate glycol units. The structure of Cu<sub>2</sub>(OH<sub>2</sub>)<sub>4</sub>[AuCl<sub>2</sub>(CN)<sub>2</sub>]<sub>4</sub>Ā·4dioxane is a 2-D coordination polymer network
with H<sub>2</sub>O-bridged CuĀ(II) centers and dioxane units hydrogen
bonded between the 2-D sheets. The intense Raman <i>v</i><sub>CN</sub> stretches for <b>1</b>, <b>2</b>, and their
adducts form distinct, signature patterns. These āantennaā
Raman <i>v</i><sub>CN</sub> stretches are an effective means
for sensing VOCs, and their characteristic patterns can be used to
identify the VOC being detected
Thermal Expansion Behavior of M<sup>I</sup>[AuX<sub>2</sub>(CN)<sub>2</sub>]āBased Coordination Polymers (M = Ag, Cu; X = CN, Cl, Br)
Two sets of <i>trans-</i>[AuX<sub>2</sub>(CN)<sub>2</sub>]<sup>ā</sup>-based coordination polymer materialsīøMĀ[AuX<sub>2</sub>(CN)<sub>2</sub>] (M = Ag; X = Cl, Br or M = Cu; X = Br) and MĀ[AuĀ(CN)<sub>4</sub>] (M = Ag, Cu)īøwere synthesized and structurally characterized
and their dielectric constants and thermal expansion behavior explored.
The MĀ[AuX<sub>2</sub>(CN)<sub>2</sub>] series crystallized in a tightly
packed, mineral-like structure featuring 1-D <i>trans-</i>[AuX<sub>2</sub>(CN)<sub>2</sub>]<sup>ā</sup>-bridged chains
interconnected via a series of intermolecular AuĀ·Ā·Ā·X
and MĀ·Ā·Ā·X (M = Ag, Cu) interactions. The MĀ[AuĀ(CN)<sub>4</sub>] series adopted a 2-fold interpenetrated 3-D cyano-bound
framework lacking any weak intermolecular interactions. Despite the
tight packing and the presence of intermolecular interactions, these
materials exhibited decreased thermal stability over unbound <i>trans-</i>[AuX<sub>2</sub>(CN)<sub>2</sub>]<sup>ā</sup> in [<sup><i>n</i></sup>Bu<sub>4</sub>N]Ā[AuX<sub>2</sub>(CN)<sub>2</sub>]. A significant dielectric constant of up to Īµ<sub>r</sub> = 36 for AgĀ[AuCl<sub>2</sub>(CN)<sub>2</sub>] (1 kHz) and
a lower Īµ<sub>r</sub> = 9.6 (1 kHz) for AgĀ[AuĀ(CN)<sub>4</sub>] were measured and interpreted in terms of their structures and
composition. A systematic analysis of the thermal expansion properties
of the MĀ[AuX<sub>2</sub>(CN)<sub>2</sub>] series revealed a negative
thermal expansion (NTE) component along the cyano-bridged chains with
a thermal expansion coefficient (Ī±<sub>CN</sub>) of ā13.7(11),
ā14.3(5), and ā11.36(18) ppmĀ·K<sup>ā1</sup> for AgĀ[AuCl<sub>2</sub>(CN)<sub>2</sub>], AgĀ[AuBr<sub>2</sub>(CN)<sub>2</sub>], and CuĀ[AuBr<sub>2</sub>(CN)<sub>2</sub>], respectively.
The AuĀ·Ā·Ā·X and AgĀ·Ā·Ā·X interactions affect
the thermal expansion similarly to metallophilic AuĀ·Ā·Ā·Au
interactions in MĀ[AuĀ(CN)<sub>2</sub>] and AuCN; replacing X = Cl with
the larger Br atoms has a less significant effect. A similar analysis
for the MĀ[AuĀ(CN)<sub>4</sub>] series (where the volume thermal expansion
coefficient, Ī±<sub>V</sub>, is 41(3) and 68.7(19) ppmĀ·K<sup>ā1</sup> for M = Ag, Cu, respectively) underscored the significance
of the effect of the atomic radius on the flexibility of the framework
and, thus, the thermal expansion properties
Color-Tunable and White-Light Luminescence in LanthanideāDicyanoaurate Coordination Polymers
The new lanthanideādicyanoaurate
coordination polymers [<sup><i>n</i></sup>Bu<sub>4</sub>N]<sub>2</sub>Ā[LnĀ(NO<sub>3</sub>)<sub>4</sub>ĀAuĀ(CN)<sub>2</sub>] (Ln = Sm, Dy) and SmĀ[AuĀ(CN)<sub>2</sub>]<sub>3</sub>Ā·3H<sub>2</sub>O were prepared and structurally
characterized and their luminescence spectra described. The emissions
of solid-solutions of [<sup><i>n</i></sup>Bu<sub>4</sub>N]<sub>2</sub>Ā[LnĀ(NO<sub>3</sub>)<sub>4</sub>ĀAuĀ(CN)<sub>2</sub>] (Ln = Ce, Sm, Eu, Tb, and Dy) were explored with an emphasis
on their capacity for luminescent color tuning and white-light emission
via the selection of composition, excitation wavelength, and temperature.
Specifically, the binary solid-solutions [<sup><i>n</i></sup>Bu<sub>4</sub>N]<sub>2</sub>Ā[Ce<sub>0.4</sub>Dy<sub>0.6</sub>(NO<sub>3</sub>)<sub>4</sub>ĀAuĀ(CN)<sub>2</sub>] and [<sup><i>n</i></sup>Bu<sub>4</sub>N]<sub>2</sub>Ā[Sm<sub>0.75</sub>Tb<sub>0.25</sub>(NO<sub>3</sub>)<sub>4</sub>ĀAuĀ(CN)<sub>2</sub>], and the ternary solid-solutions [<sup><i>n</i></sup>Bu<sub>4</sub>N]<sub>2</sub>Ā[Ce<sub>0.2</sub>Sm<sub>0.6</sub>ĀTb<sub>0.2</sub>(NO<sub>3</sub>)<sub>4</sub>ĀAuĀ(CN)<sub>2</sub>] and [<sup><i>n</i></sup>Bu<sub>4</sub>N]<sub>2</sub>Ā[Ce<sub>0.33</sub>Eu<sub>0.17</sub>ĀTb<sub>0.5</sub>(NO<sub>3</sub>)<sub>4</sub>ĀAuĀ(CN)<sub>2</sub>], were prepared and
examined in terms of suitability for color-tuning capacity. These
results showcase that the emission from the [<sup><i>n</i></sup>Bu<sub>4</sub>N]<sub>2</sub>Ā[LnĀ(NO<sub>3</sub>)<sub>4</sub>ĀAuĀ(CN)<sub>2</sub>] framework has the capacity to be tuned
to extremes corresponding to deep reds (CIE coordinates 0.65, 0.35),
greens (0.28, 0.63), and deep blue/violet (0.16, 0.06) as well as
white (0.31, 0.33). Conversely, the emission of the SmĀ[AuĀ(CN)<sub>2</sub>]<sub>3</sub>Ā·3H<sub>2</sub>O framework, when doped with
the green phosphor TbĀ(III), changes only slightly because of the predominantly
AuĀ(I)-based emission and SmĀ(III) ā AuĀ(I) energy transfer
Copper(II) Dihalotetracyanoplatinate(IV) Coordination Polymers and Their Vapochromic Behavior
The coordination
polymers [CuĀ(H<sub>2</sub>O)<sub>2</sub>(Ī¼<sub>2</sub>-NC)<sub>4</sub>PtX<sub>2</sub>] (X = Cl, Br) form networks of square grid
sheets that align in a staggered manner with one another via weak
XĀ·Ā·Ā·X interactions. Upon stepwise dehydration, the
layers fuse, forming a 3-D network of distorted cubes. The materials
were tested for visible vapochromic, Raman, and IR response to dimethyl
sulfoxide, <i>N,N</i>-dimethylformamide, and pyridine. Analyte-bound
coordination polymers of the form CuĀ(analyte)<sub>2</sub>[PtX<sub>2</sub>(CN)<sub>4</sub>] were structurally characterized by PXRD
and found to form layers of square grids that align through XĀ·Ā·Ā·X
interactions. The reaction of [CuĀ(H<sub>2</sub>O)<sub>2</sub>(Ī¼<sub>2</sub>-NC)<sub>4</sub>PtX<sub>2</sub>] with concentrated aqueous
NH<sub>3</sub> generated [PtBrĀ(CN)<sub>4</sub>(NH<sub>3</sub>)]<sup>ā</sup> and [PtClĀ(CN)<sub>4</sub>(OH)]<sup>2ā</sup> anions that were incorporated into 1-D chain structures. UVāvisible
reflectance data show that a combination of shifting dād transitions
and the visible BrāPt LMCT absorption band in [CuĀ(H<sub>2</sub>O)<sub>2</sub>(Ī¼<sub>2</sub>-NC)<sub>4</sub>PtBr<sub>2</sub>] results in a greater vapochromic effect in comparison to that in
chlorine-containing analogues
Structural Design Parameters for Highly Birefringent Coordination Polymers
A series of coordination polymer
materials incorporating the highly anisotropic 2-(2-pyridyl)-1,10-phenanthroline
(phenpy) building block have been synthesized and structurally characterized.
MĀ(phenpy)Ā[AuĀ(CN)<sub>2</sub>]<sub>2</sub> (M = Cd, Mn) are isostructural
and form a 1-D chain through bridging [AuĀ(CN)<sub>2</sub>]<sup>ā</sup> units and extend into a 2-D sheet through aurophilic interactions.
MĀ(phenpy)Ā(H<sub>2</sub>O)Ā[AuĀ(CN)<sub>2</sub>]<sub>2</sub>Ā·2H<sub>2</sub>O (M = Cd, Mn, and Zn) are also isostructural but differ from
the first set via the inclusion of a water molecule into the coordination
sphere, resulting in a 1-D topology through aurophilic interactions.
InĀ(phenpy)Ā(Cl)<sub>2</sub>[AuĀ(CN)<sub>2</sub>]Ā·0.5H<sub>2</sub>O forms a dimer through bridging chlorides and contains a free [AuĀ(CN)<sub>2</sub>]<sup>ā</sup> unit. In the plane of the primary crystal
growth direction, the birefringence values (Ī<i>n</i>) of 0.37(2) (CdĀ(phenpy)Ā[AuĀ(CN)<sub>2</sub>]<sub>2</sub>), 0.50(3)
(InĀ(phenpy)Ā(Cl)<sub>2</sub>[AuĀ(CN)<sub>2</sub>]Ā·0.5H<sub>2</sub>O), 0.56(3) and 0.59(6) (MĀ(phenpy)Ā(H<sub>2</sub>O)Ā[AuĀ(CN)<sub>2</sub>]<sub>2</sub>Ā·2H<sub>2</sub>O M = Cd and Zn, respectively) were
determined. Ī², a structural parameter defined by phenpy units
rotated in the <i>A</i>ā<i>C</i> plane
relative to the light propagation (<i>C</i>) direction,
was found to correlate to Ī<i>n</i> magnitudes. The
addition of a carbonācarbon double bond to terpy has increased
the molecular polarizability anisotropy of the building block, and
all structures have reduced deviation from planarity in comparison
to terpy and terpy derivative structures, leading to these higher
Ī<i>n</i> values, which are among the highest reported
for crystalline solids
An Extremely Air-Stable 19Ļ Porphyrinoid
A one-electron reduced species of
a cationic phosphorusĀ(V) tetraazaporphyrin
complex has been isolated as an air-stable solid. Cyclic voltammetry
and magnetic measurements showed the species to be a neutral Ļ
radical, and the solid state structure was elucidated by single crystal
X-ray diffraction analysis. Magnetic circular dichroism spectroscopy
and theoretical calculations also support a 19Ļ electron conjugated
electronic circuit
Heterobimetallic Coordination Polymers Based on the [Pt(SCN)<sub>4</sub>]<sup>2ā</sup> and [Pt(SeCN)<sub>4</sub>]<sup>2ā</sup> Building Blocks
New complexes and
the first coordination polymers containing [PtĀ(SCN)<sub>4</sub>]<sup>2ā</sup> of the type [MĀ(L)<sub><i>x</i></sub>]Ā[PtĀ(SCN)<sub>4</sub>] (where L = 2,2ā²-bipyridine (bipy), <i>x</i> = 2, M = CoĀ(II), NiĀ(II), CuĀ(II); L = ethylenediamine (en), <i>x</i> = 2, M = NiĀ(II), CuĀ(II); L = <i>N</i>,<i>N</i>,<i>N</i>ā²,<i>N</i>ā²-tetramethylethylenediamine
(tmeda), <i>x</i> = 1, M = CuĀ(II); L = 2,2ā²;6ā²,2ā³-terpyridine
(terpy), <i>x</i> = 1, M = MnĀ(II), CoĀ(II); L = 1,10-phenanthroline
(phen), <i>x</i> = 2, M = PbĀ(II)) were prepared by reacting
the appropriate metalāligand cations with K<sub>2</sub>[PtĀ(SCN)<sub>4</sub>] and structurally characterized. [MĀ(bipy)<sub>2</sub>PtĀ(SCN)<sub>4</sub>]<sub>2</sub>Ā·2MeOH (M = Co (<b>1</b>), Cu (<b>4</b>)) consist of supramolecular tetranuclear distorted squares
containing two [MĀ(bipy)<sub>2</sub>]<sup>2+</sup> and two [PtĀ(SCN)<sub>4</sub>]<sup>2+</sup> units. [CuĀ(bipy)<sub>2</sub>(NCS)]<sub>2</sub>[PtĀ(SCN)<sub>4</sub>] (<b>6</b>) is a double salt of the [PtĀ(SCN)<sub>4</sub>]<sup>2ā</sup> anion and two [CuĀ(bipy)Ā(NCS)]<sup>+</sup> cations. [CuĀ(en)<sub>2</sub>PtĀ(SCN)<sub>4</sub>] (<b>7</b>, <b>8</b>) are 1-D coordination polymers that are coordinated
in either cis or trans fashion at the [PtĀ(SCN)<sub>4</sub>]<sup>2ā</sup> unit, for <b>7</b> and <b>8</b>, respectively. Complexes
[CuĀ(en)<sub>2</sub>PtĀ(SeCN)<sub>4</sub>] (<b>9</b>) and [NiĀ(en)<sub>2</sub>PtĀ(SCN)<sub>4</sub>] (<b>10</b>) are similar to <b>8</b> and <b>7</b>, respectively, but complex <b>9</b> (prepared using (<sup>n</sup>Bu<sub>4</sub>N)<sub>2</sub>[PtĀ(SeCN)<sub>4</sub>]) also presents intermolecular SeāSe interactions
which resulted in an increased dimensionality. Compounds [MĀ(terpy)ĀPtĀ(SCN)<sub>4</sub>] (M = Mn (<b>11</b>), Co (<b>13</b>)) involve
2-D sheets of [MĀ(terpy)]<sup>2+</sup> and [PtĀ(SCN)<sub>4</sub>]<sup>2ā</sup> units, whereas [MnĀ(terpy)<sub>2</sub>]Ā[PtĀ(SCN)<sub>4</sub>] (<b>12</b>) is a double salt of one [MnĀ(terpy)<sub>2</sub>]<sup>2+</sup> unit and one [PtĀ(SCN)<sub>4</sub>]<sup>2ā</sup>. [CuĀ(tmeda)ĀPtĀ(SCN)<sub>4</sub>] (<b>14</b>) contains a five-coordinate
Cu<sup>2+</sup> metal center coordinated to one tmeda ligand and three
different [PtĀ(SCN)<sub>4</sub>]<sup>2ā</sup> units, resulting
in 2-D sheets. [PbĀ(phen)<sub>2</sub>PtĀ(SCN)<sub>4</sub>] (<b>15</b>) contains an 8-coordinate Pb<sup>2+</sup> metal center coordinated
to two phen ligands and four [PtĀ(SCN)<sub>4</sub>]<sup>2ā</sup>, generating a 3-D network in the solid state. Structural correlations
were established between the ancillary ligand, the choice of metal,
the structure of the [PtĀ(SCN)<sub>4</sub>]<sup>2ā</sup> building
block, and the resulting dimensionality of the coordination polymers
Interpreting Effects of Structure Variations Induced by Temperature and Pressure on Luminescence Spectra of Platinum(II) Bis(dithiocarbamate) Compounds
Luminescence spectra of two square-planar
dithiocarbamate complexes of platinumĀ(II) with different steric bulk,
platinumĀ(II) bisĀ(dimethyldithiocarbamate) (PtĀ(MeDTC)<sub>2</sub>)
and platinumĀ(II) bisĀ(diĀ(<i>o</i>-pyridyl)Ādithiocarbamate)
(PtĀ(dopDTC)<sub>2</sub>), are presented at variable temperature and
pressure. The spectra show broad dād luminescence transitions
with maxima at approximately 13500 cm<sup>ā1</sup> (740 nm).
Variations of the solid-state spectra with temperature and pressure
reveal intrinsic differences due to subtle variations of molecular
and crystal structures, reported at 100 and 296 K for PtĀ(dopDTC)<sub>2</sub>. Luminescence maxima of PtĀ(MeDTC)<sub>2</sub> shift to higher
energy as temperature increases by +320 cm<sup>ā1</sup> for
an increase by 200 K, mainly caused by a bandwidth increase from 3065
to 4000 cm<sup>ā1</sup> on the high-energy side of the band
over the same temperature range. Luminescence maxima of PtĀ(dopDTC)<sub>2</sub> shift in the opposite direction by ā460 cm<sup>ā1</sup> for a temperature increase by 200 K. The bandwidth of approximately
2900 cm<sup>ā1</sup> does not vary with temperature. Both ground
and emitting-state properties and subtle structural differences between
the two compounds lead to this different behavior. Luminescence maxima
measured at variable pressure show shifts to higher energy by +47
Ā± 3 and +11 Ā± 1 cm<sup>ā1</sup>/kbar, for PtĀ(MeDTC)<sub>2</sub> and PtĀ(dopDTC)<sub>2</sub>, respectively, a surprising difference
by a factor of 4. The crystal structures indicate that decreasing
intermolecular interactions with increasing pressure are likely to
contribute to the exceptionally high shift for PtĀ(MeDTC)<sub>2</sub>
Interpreting Effects of Structure Variations Induced by Temperature and Pressure on Luminescence Spectra of Platinum(II) Bis(dithiocarbamate) Compounds
Luminescence spectra of two square-planar
dithiocarbamate complexes of platinumĀ(II) with different steric bulk,
platinumĀ(II) bisĀ(dimethyldithiocarbamate) (PtĀ(MeDTC)<sub>2</sub>)
and platinumĀ(II) bisĀ(diĀ(<i>o</i>-pyridyl)Ādithiocarbamate)
(PtĀ(dopDTC)<sub>2</sub>), are presented at variable temperature and
pressure. The spectra show broad dād luminescence transitions
with maxima at approximately 13500 cm<sup>ā1</sup> (740 nm).
Variations of the solid-state spectra with temperature and pressure
reveal intrinsic differences due to subtle variations of molecular
and crystal structures, reported at 100 and 296 K for PtĀ(dopDTC)<sub>2</sub>. Luminescence maxima of PtĀ(MeDTC)<sub>2</sub> shift to higher
energy as temperature increases by +320 cm<sup>ā1</sup> for
an increase by 200 K, mainly caused by a bandwidth increase from 3065
to 4000 cm<sup>ā1</sup> on the high-energy side of the band
over the same temperature range. Luminescence maxima of PtĀ(dopDTC)<sub>2</sub> shift in the opposite direction by ā460 cm<sup>ā1</sup> for a temperature increase by 200 K. The bandwidth of approximately
2900 cm<sup>ā1</sup> does not vary with temperature. Both ground
and emitting-state properties and subtle structural differences between
the two compounds lead to this different behavior. Luminescence maxima
measured at variable pressure show shifts to higher energy by +47
Ā± 3 and +11 Ā± 1 cm<sup>ā1</sup>/kbar, for PtĀ(MeDTC)<sub>2</sub> and PtĀ(dopDTC)<sub>2</sub>, respectively, a surprising difference
by a factor of 4. The crystal structures indicate that decreasing
intermolecular interactions with increasing pressure are likely to
contribute to the exceptionally high shift for PtĀ(MeDTC)<sub>2</sub>