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1.
Org Biomol Chem ; 18(15): 2861-2865, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32215434

RESUMO

The elusive cis tautomer of free-base porphyrins has recently been isolated and structurally characterized in the form of a supramolecular complex. The question as to whether a suitable set of peripheral substituents might lead to a stable cis tautomer in the absence of supramolecular interactions, however, remains unanswered and is one we have attempted to address here by means of density functional theory calculations. The fact that many antipodally ß-tetrasubstituted tetraphenylporphyrin derivatives exhibit localized central protons attached to the ß-unsubstituted pyrrole rings led us to surmise that ß-tetrasubstitution of adjacent pyrrole rings might lead to a porphyrin cis tautomer, an idea that proved fruitful. Indeed, for the "adjacently" substituted tetraphenylporphyrin derivative H2[adj-(CF3)4(CH3)4TPP], the global energy minimum proved to be a highly saddled cis tautomer, with the trans tautomer about 0.07 eV higher in energy. It is important to underscore, however, that the asymmetric ß-substitution pattern is far from the only factor contributing to the stability of the cis tautomer for this porphyrin. A strongly saddled conformation resulting from meso-ß steric interactions also helps alleviate the repulsion between the two central NH protons, thereby stabilizing the cis tautomer relative to the trans.

2.
Chem Commun (Camb) ; 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32100738

RESUMO

Crystals of a Cu complex of the macrocyclic Schiff-base calixpyrrole or 'Pacman' ligand, Cu2(L), do not contain any solvent-accessible void space at ambient pressure, but adsorb neon at 4.67 GPa, forming Cu2(L)·3.5Ne.

3.
Sci Rep ; 9(1): 14459, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31595017

RESUMO

The high-pressure and high-temperature structural and chemical stability of ruthenium has been investigated via synchrotron X-ray diffraction using a resistively heated diamond anvil cell. In the present experiment, ruthenium remains stable in the hcp phase up to 150 GPa and 960 K. The thermal equation of state has been determined based upon the data collected following four different isotherms. A quasi-hydrostatic equation of state at ambient temperature has also been characterized up to 150 GPa. The measured equation of state and structural parameters have been compared to the results of ab initio simulations performed with several exchange-correlation functionals. The agreement between theory and experiments is generally quite good. Phonon calculations were also carried out to show that hcp ruthenium is not only structurally but also dynamically stable up to extreme pressures. These calculations also allow the pressure dependence of the Raman-active E2g mode and the silent B1g mode of Ru to be determined.

4.
Molecules ; 24(10)2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31137795

RESUMO

The crystal structure of 4-iodobenzonitrile, which is monoclinic (space group I2/a) under ambient conditions, contains chains of molecules linked through C≡N···I halogen-bonds. The chains interact through CH···I, CH···N and π-stacking contacts. The crystal structure remains in the same phase up to 5.0 GPa, the b axis compressing by 3.3%, and the a and c axes by 12.3 and 10.9 %. Since the chains are exactly aligned with the crystallographic b axis these data characterise the compressibility of the I···N interaction relative to the inter-chain interactions, and indicate that the halogen bond is the most robust intermolecular interaction in the structure, shortening from 3.168(4) at ambient pressure to 2.840(1) Å at 5.0 GPa. The π∙∙∙π contacts are most sensitive to pressure, and in one case the perpendicular stacking distance shortens from 3.6420(8) to 3.139(4) Å. Packing energy calculations (PIXEL) indicate that the π∙∙∙π interactions have been distorted into a destabilising region of their potentials at 5.0 GPa. The structure undergoes a transition to a triclinic ( P 1 ¯ ) phase at 5.5 GPa. Over the course of the transition, the initially colourless and transparent crystal darkens on account of formation of microscopic cracks. The resistance drops by 10% and the optical transmittance drops by almost two orders of magnitude. The I···N bond increases in length to 2.928(10) Å and become less linear [

Assuntos
Halogênios/química , Nitrilos/química , Pressão , Cristalização , Diamante/química , Dimerização , Elétrons , Ouro/química , Conformação Molecular , Fônons , Espectrofotometria Ultravioleta , Análise Espectral Raman , Termodinâmica
5.
Rev Sci Instrum ; 89(8): 083903, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30184656

RESUMO

A new design for a double-sided high-pressure diamond anvil cell laser heating set-up is described. The prototype is deployed at beamline 12.2.2 of the Advanced Light Source at Lawrence Berkeley National Lab. Our compact design features shortened mechanical lever arms, which results in more stable imaging optics, and thus more user friendly and more reliable temperature measurements based on pyrometry. A modification of the peak scaling method was implemented for pyrometry, including an iterative method to determine the absolute peak temperature, thus allowing for quasi-real time temperature mapping of the actual hotspot within a laser-heated diamond anvil cell without any assumptions on shape, size, and symmetry of the hotspot and without any assumptions to the relationship between fitted temperature and peak temperature. This is important since we show that the relationship between peak temperature and temperature obtained by fitting the Planck function against the thermal emission spectrum averaged over the entire hotspot is not constant but depends on variable fitting parameters (in particular, the size and position of the fitting window). The accuracy of the method is confirmed through measuring melting points of metal wires at ambient pressure. Having absolute temperature maps in real time allows for more differentiated analyses of laser heating experiments. We present such an example of the pressure variations within a heated hotspot of AgI at a loaded base pressure of 3.8 GPa.

6.
Inorg Chem ; 57(4): 2002-2012, 2018 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-29400457

RESUMO

Single crystals of a complex Zintl compound with the composition Na4Ge13 were synthesized for the first time using a high-pressure/high-temperature approach. Single-crystal diffraction of synchrotron radiation revealed a hexagonal crystal structure with P6/m space group symmetry that is composed of a three-dimensional sp3 Ge framework punctuated by small and large channels along the crystallographic c axis. Na atoms are inside hexagonal prism-based Ge cages along the small channels, while the larger channels are occupied by layers of disordered sixfold Na rings, which are in turn filled by disordered [Ge4]4- tetrahedra. This compound is the same as "Na1-xGe3+z" reported previously, but the availability of single crystals allowed for more complete structural determination with a formula unit best described as Na4Ge12(Ge4)0.25. The compound is the first known example of a guest-host structure where discrete Zintl polyanions are confined inside the channels of a three-dimensional covalent framework. These features give rise to temperature-dependent disorder, as confirmed by first-principles calculations and physical properties measurements. The availability of single-crystal specimens allowed for measurement of the intrinsic low-temperature transport properties of this material and revealed its semiconductor behavior, which was corroborated by theoretical calculations.

7.
ChemistryOpen ; 6(3): 402-409, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28638773

RESUMO

Presented herein is a study of the acid-induced demetalation of two sterically hindered copper corroles, Cu ß-octabromo-meso-triphenylcorrole (Cu[Br8TPC]) and ß-octakis(trifluoromethyl)-meso-tris(p-methoxyphenyl)corrole (Cu[(CF3)8TpOMePC]). Unlike reductive demetalation, which affords the free-base ß-octabromocorrole, demetalation of Cu[Br8TPC] under non- reductive conditions (CHCl3/H2SO4) resulted in moderate yields of free-base 5- and 10-hydroxy isocorroles. The isomeric free bases could be complexed to CoII and NiII, affording stable complexes. Only reductive demetalation was found to work for Cu[(CF3)8TpOMePC], affording a highly saddled, hydrated corrole, H3[5-OH,10-H-(CF3)8TpOMePC], where the elements of water had added across C5 and C10. Interaction of this novel free base with CoII resulted in Co[iso-10-H-[CF3)8TpOMePC], a CoII 10-hydro isocorrole. The new metal complexes were all characterized by single-crystal X-ray diffraction analysis and, despite their sterically hindered nature, were found to exhibit almost perfectly planar isocorrole cores.

8.
Dalton Trans ; 45(46): 18484-18493, 2016 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-27603554

RESUMO

Tetraalkyldiglycolamide (TRDGA) ligands have potential utilization for the separation of actinide and lanthanide ions in the nuclear industry as chelates in aqueous solution if water-soluble or as extractants in organic solvents if water-insoluble. Here, a spectral titration method is extensively applied to investigating the complexation of fluorescent Sm(iii), Eu(iii), and Tb(iii) with TRDGA ligands in aqueous solutions and a solvent extraction system. In aqueous solutions using N,N,N',N'-tetramethyldiglycolamide (TMDGA, LI) as chelate, three successive complex species of Ln(iii), including [LnLI]3+, [LnL]3+, and [LnL]3+, are identified for each Ln(iii) (Ln = Sm, Eu, and Tb), and their stability constants are determined with fluorescence spectral titration method at 25 °C in 1 M NaNO3. The coordination mode in [LnL]3+ is illustrated by single-crystal structures of the solid compounds LnL(ClO4)3 (Ln = Sm, Eu, Tb, and LI = TMDGA) grown from aqueous solutions by slow evaporation. The crystal structures show that in the complexes Ln(iii) ions are coordinated by nine oxygen atoms from three tridentate LI ligands in a distorted tricapped trigonal prism geometry. To provide parallels to solvent extraction chemistry, the extracted Ln(iii) complexes with N,N'-dimethyl-N,N'-dioctyldiglycolamide (DMDODGA, LII, a lipophilic analogue of TMDGA) are prepared, and the fluorescence spectra are collected as well for comparison. The fluorescence spectra of the extracted Ln(iii) complexes with LII in an organic phase of 40-60% (v/v) n-octanol-kerosene are nearly identical to the corresponding deconvoluted spectra of [LnL]3+ in aqueous solution. The similarity in fluorescence spectra suggests that Ln(iii) ion in the extracted complexes is also coordinated by three tridentate LII ligands and that the nitrate anions acting just as counterions do not directly bond to Ln(iii) in the organic phase of solvent extraction.

9.
ACS Cent Sci ; 2(4): 201-9, 2016 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-27163050

RESUMO

We report the first high-pressure single-crystal structures of hybrid perovskites. The crystalline semiconductors (MA)PbX3 (MA = CH3NH3 (+), X = Br(-) or I(-)) afford us the rare opportunity of understanding how compression modulates their structures and thereby their optoelectronic properties. Using atomic coordinates obtained from high-pressure single-crystal X-ray diffraction we track the perovskites' precise structural evolution upon compression. These structural changes correlate well with pressure-dependent single-crystal photoluminescence (PL) spectra and high-pressure bandgaps derived from density functional theory. We further observe dramatic piezochromism where the solids become lighter in color and then transition to opaque black with compression. Indeed, electronic conductivity measurements of (MA)PbI3 obtained within a diamond-anvil cell show that the material's resistivity decreases by 3 orders of magnitude between 0 and 51 GPa. The activation energy for conduction at 51 GPa is only 13.2(3) meV, suggesting that the perovskite is approaching a metallic state. Furthermore, the pressure response of mixed-halide perovskites shows new luminescent states that emerge at elevated pressures. We recently reported that the perovskites (MA)Pb(Br x I1-x )3 (0.2 < x < 1) reversibly form light-induced trap states, which pin their PL to a low energy. This may explain the low voltages obtained from solar cells employing these absorbers. Our high-pressure PL data indicate that compression can mitigate this PL redshift and may afford higher steady-state voltages from these absorbers. These studies show that pressure can significantly alter the transport and thermodynamic properties of these technologically important semiconductors.

10.
Angew Chem Int Ed Engl ; 55(15): 4671-3, 2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-26970221

RESUMO

Efficient separation processes for recovering uranium and plutonium from spent nuclear fuel are essential to the development of advanced nuclear fuel cycles. The performance characteristics of a new salt-free complexing and reducing reagent, glutarimidedioxime (H2A), are reported for recovering plutonium in a PUREX process. With a phase ratio of organic to aqueous of up to 10:1, plutonium can be effectively stripped from 30% tributyl phosphate (TBP) in kerosene into 1 M HNO3 with H2A. The complexation-reduction mechanism is illustrated with the combination of UV/Vis absorption spectra and the crystal structure of a Pu(IV) complex with the reagent. The fast stripping rate and the high efficiency for stripping Pu(IV), through the complexation-reduction mechanism, is suitable for use in centrifugal contactors with very short contact/resident times, thereby offering significant advantages over conventional processes.

11.
IUCrJ ; 3(Pt 5): 367-376, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28461897

RESUMO

We report a molecular crystal that exhibits four successive phase transitions under hydro-static pressure, driven by aurophilic interactions, with the ground-state structure re-emerging at high pressure. The effect of pressure on two polytypes of tris(µ2-3,5-diiso-propyl-1,2,4-triazolato-κ2N1:N2)trigold(I) (denoted Form-I and Form-II) has been analysed using luminescence spectroscopy, single-crystal X-ray diffraction and first-principles computation. A unique phase behaviour was observed in Form-I, with a complex sequence of phase transitions between 1 and 3.5 GPa. The ambient C2/c mother cell transforms to a P21/n phase above 1 GPa, followed by a P21/a phase above 2 GPa and a large-volume C2/c supercell at 2.70 GPa, with the previously observed P21/n phase then reappearing at higher pressure. The observation of crystallographically identical low- and high-pressure P21/n phases makes this a rare example of a re-entrant phase transformation. The phase behaviour has been characterized using detailed crystallographic theory and modelling, and rationalized in terms of molecular structural distortions. The dramatic changes in conformation are correlated with shifts of the luminescence maxima, from a band maximum at 14040 cm-1 at 2.40 GPa, decreasing steeply to 13550 cm-1 at 3 GPa. A similar study of Form-II displays more conventional crystallographic behaviour, indicating that the complex behaviour observed in Form-I is likely to be a direct consequence of the differences in crystal packing between the two polytypes.

12.
Dalton Trans ; 45(2): 681-9, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26619363

RESUMO

The first FeNO octabromocorroles have been synthesized including four ß-octabromo-meso-tris(p-X-phenyl)corrole derivatives Fe[Br8TpXPC](NO) (X = CF3, H, CH3, OCH3) and the ß-octabromo-meso-tris(pentafluorophenyl)corrole complex, Fe[Br8TPFPC](NO). The last complex, which proved amenable to single-crystal X-ray structure determination, exhibits the geometry parameters: Fe-N(O) 1.643(8) Å, N-O 1.158(9) Å, and a FeNO angle of 176.4(6)°. The more electron-deficient complexes exhibit increased instability with respect to NO loss and also higher infrared NO stretching frequencies (νNO). Interestingly, DFT calculations and IR marker bands indicate a noninnocent {FeNO}(7)-(corrole˙(2-)) formulation for all FeNO corroles, both ß-H8 and ß-Br8, with essentially the same degree of corrole radical character. Instead, an electron-deficient corrole appears to exert a field effect resulting in reduced Fe-to-NO backdonation, which accounts for both the increased instability with respect to NO loss and the higher νNO's.

13.
Dalton Trans ; 44(42): 18469-74, 2015 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-26442451

RESUMO

Complexation of Am(iii) with tetramethyl-3-oxa-glutaramide (TMOGA, L(I)) is studied by spectrophotometric titrations and single crystal X-ray diffraction. Three successive complex species, [AmL(I)](3+), [AmL](3+), and [AmL](3+), have been identified and their stability constants are calculated to be 3.71 ± 0.012, 5.95 ± 0.021, and 6.93 ± 0.034 respectively, from the absorption spectra collected from the titrations of Am(iii) with L(I) at 25 °C in 1 M NaNO3. Single crystals of AmL(ClO4)3 have been grown from a HClO4 solution containing Am(3+) and L(I). The crystal structure of AmL(ClO4)3 shows that Am(iii) is coordinated by nine oxygen atoms from three L(I) ligands. The deconvoluted UV-Vis absorption spectrum of [AmL](3+) in aqueous solution is nearly identical to the diffusion reflectance spectrum of AmL(ClO4)3 in the solid state, indicating that the coordination geometry of the complexes is nearly the same. In addition, to provide parallels to solvent exaction, the extracted Am(iii) complex with N,N'-dimethyl-N,N'-dioctyl-3-oxa-glutaramide (DMDOOGA, L(II)) is also prepared and studied using spectrophotometry. The similarity in UV-Vis absorption of the extracted complex of Am(iii) with L(II) and [AmL](3+) suggests that the Am(iii) ion is also coordinated by three tridentate L(II) ligands existing as [AmL](3+) in the organic phase of solvent extraction.

14.
Chemistry ; 21(47): 16839-47, 2015 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-26345592

RESUMO

A silver ß-octabromo-meso-triarylcorrole has been found to exhibit a strongly saddled geometry, providing the first instance of a strongly saddled corrole complex involving a metal other than copper. The Soret maxima of the Ag octabromocorroles also redshift markedly in response to increasingly electron-donating para substituents on the meso-aryl groups. In both these respects, the Ag octabromocorroles differ from simple Ag triarylcorrole derivatives, which exhibit only mild saddling and substituent-insensitive Soret maxima. These results have been rationalized in terms of an innocent M(III)-corrole(3-) description for the simple Ag corroles and a noninnocent M(II)-corrole(·2-) description for the Ag octabromocorroles. In contrast, all copper corroles are thought to be noninnocent, while all gold corroles are innocent. Uniquely among metallocorroles, silver corroles thus seem poised on a knife-edge, so to speak, between innocent and noninnocent electronic structures and may tip either way, depending on the exact nature of the corrole ligand.

15.
J Inorg Biochem ; 153: 162-166, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26354820

RESUMO

In spite of significant applications as starting materials for a variety of metallocorrole derivatives, free-base ß-octabromo-meso-triarylcorroles continue to be viewed as inaccessible. The reasons range from the need for tedious column-chromatographic purification to limitations of the reductive demetallation protocol for selected systems. Here we report that column chromatography may be entirely avoided for a number of ß-octabromo-meso-tris(p-X-phenyl)corrole derivatives, where X=CF3, NO2, F, H, CH3, and OCH3; instead, analytically pure products may be obtained by recrystallization from chloroform/methanol. In addition, we have presented an optimized synthesis of the heretofore inaccessible, sterically hindered ligand ß-octabromo-meso-tris(2,6-dichlorophenyl)corrole, H3[Br8TDCPC], via reductive demetallation of the corresponding Mn(III) complex. With our earlier report of ß-octabromo-meso-tris(pentafluorophenyl)corrole, H3[Br8TPFPC], a comprehensive set of optimized synthetic protocols are thus in place for a good number of ß-octabromo-meso-triarylcorrole ligands. Furthermore, we have illustrated the use of these ligands by synthesizing the iron complexes Fe[Br8TDCPC]Cl and Fe[Br8TDCPC](py)2, of which the latter lent itself to single-crystal X-ray structure determination.


Assuntos
Metaloporfirinas/síntese química , Cobre/química , Cristalização , Ferro/química , Ligantes , Metaloporfirinas/química , Conformação Molecular
16.
Chemistry ; 21(31): 11212-8, 2015 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-26121216

RESUMO

The central Mn(II) ions in a series of calix[4]arene-stabilised butterflies can be sequentially replaced with Ln(III) ions, maintaining the structural integrity of the molecule but transforming its magnetic properties. The replacement of Mn(II) for Gd(III) allows for the examination of the transferability of spin-Hamiltonian parameters within the family as well as permitting their reliable determination. The introduction of the 4f ions results in weaker intramolecular magnetic exchange, an increase in the number of low-lying excited states, and an increase in magnetisation relaxation, highlighting the importance of exchange over single-ion anisotropy for the observation of SMM behaviour in this family of complexes. The presence of the [TM(II/III) (TBC[4])(OH)(solvent)] metalloligand (TM=transition metal, TBC=p-tBu-calix[4]arene) suggests that magnetic calix[n]arene building blocks can be employed to encapsulate a range of different "guests" within structurally robust "hosts".

17.
J Phys Chem A ; 119(14): 3452-7, 2015 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-25819028

RESUMO

The molecular structures of free-base corroles are illustrative of a variety of bonded and nonbonded interactions including aromaticity, intra- as well as intermolecular hydrogen bonding, steric interactions among multiple NH hydrogens within a congested central cavity, and the effects of peripheral substituents. Against this backdrop, an X-ray structure of 2,3,7,8,12,13,17,18-octabromo-5,10,15-tris(pentafluorophenyl)corrole, H3[Br8TPFPCor], corresponding to a specific tautomer, has been found to exhibit the strongest nonplanar distortions observed to date for any free-base corrole structure. Two adjacent N-protonated pyrrole rings are tilted with respect to each other by approximately 97.7°, while the remainder of the molecule is comparatively planar. Dispersion-corrected DFT calculations were undertaken to investigate to what extent the strong nonplanar distortions can be attributed to steric effects of the peripheral substituents. For meso-triphenylcorrole, DFT calculations revealed nonplanar distortions that are only marginally less pronounced than those found for H3(Br8TPFPCor). A survey of X-ray structures of sterically unhindered corroles also uncovered additional examples of rather strong nonplanar distortions. Detailed potential energy calculations as a function of different saddling dihedrals also emphasized the softness of the distortions. Because of nonplanar distortions, free-base corrole structures are chiral. For H3[Br8TPFPCor], DFT calculations led to an estimate of 15 kcal/mol (0.67 eV) as the activation barrier for enantiomerization of the free-base structures, which is significantly higher than the barrier for NH tautomerism calculated for this molecule, about 5 kcal/mol (0.2 eV). In summary, steric crowding of the internal NH hydrogens appears to provide the main driving force for nonplanar distortions of meso-triarylcorroles; the presence of additional ß-substituents adds marginally to this impetus.

18.
Chemistry ; 21(7): 2804-12, 2015 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-25641542

RESUMO

Methylene-bridged calix[4]arenes have emerged as extremely versatile ligand supports in the formation of new polymetallic clusters possessing fascinating magnetic properties. Metal ion binding rules established for this building block allow one to partially rationalise the complex assembly process. The ability to covalently link calix[4]arenes at the methylene bridge provides significantly improved control over the introduction of different metal centres to resulting cluster motifs. Clusters assembled from bis-calix[4]arenes and transition metal ions or 3d-4f combinations display characteristic features of the analogous calix[4]arene supported clusters, thereby demonstrating an enhanced and rational approach towards the targeted synthesis of complex and challenging structures.

19.
Chemistry ; 20(51): 16933-42, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25331304

RESUMO

A systematic investigation into the relationship between the solid-state luminescence and the intermolecular Au⋅⋅⋅Au interactions in a series of pyrazolate-based gold(I) trimers; tris(µ2 -pyrazolato-N,N')-tri-gold(I) (1), tris(µ2 -3,4,5- trimethylpyrazolato-N,N')-tri-gold(I) (2), tris(µ2 -3-methyl-5-phenylpyrazolato-N,N')-tri-gold(I) (3) and tris(µ2 -3,5-diphenylpyrazolato-N,N')-tri-gold(I) (4) has been carried out using variable temperature and high pressure X-ray crystallography, solid-state emission spectroscopy, Raman spectroscopy and computational techniques. Single-crystal X-ray studies show that there is a significant reduction in the intertrimer Au⋅⋅⋅Au distances both with decreasing temperature and increasing pressure. In the four complexes, the reduction in temperature from 293 to 100 K is accompanied by a reduction in the shortest intermolecular Au⋅⋅⋅Au contacts of between 0.04 and 0.08 Å. The solid-state luminescent emission spectra of 1 and 2 display a red shift with decreasing temperature or increasing pressure. Compound 3 does not emit under ambient conditions but displays increasingly red-shifted luminescence upon cooling or compression. Compound 4 remains emissionless, consistent with the absence of intermolecular Au⋅⋅⋅Au interactions. The largest pressure induced shift in emission is observed in 2 with a red shift of approximately 630 cm(-1) per GPa between ambient and 3.80 GPa. The shifts in all the complexes can be correlated with changes in Au⋅⋅⋅Au distance observed by diffraction.

20.
Chem Commun (Camb) ; 50(76): 11093-6, 2014 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-24911328

RESUMO

Platinum has been inserted into corroles for the first time and three oxidized Pt(IV)(corrole˙(2-))ArAr' complexes have been structurally characterized. The Soret maxima of these complexes exhibit an unusually strong dependence on the meso-aryl substituents on the corrole, indicating aryl → corrole˙(2-) charge transfer character in these transitions.

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