Solid-State Replacement in the Polyhedra of Cu, Ni, and Co upon Dehydration/Rehydration Processes Associated with a Color Change in Three Isomorphous Materials with 5,5'-Indigodisulfonate.

The significance of thermochromic materials in a wide range of applications makes their research and development highly desirable. Herein, three new thermochromic isomorphous supramolecular materials based on the 5,5'-indigodisulfonate ion of the indigo carmine dye, with formulas [Cu(HO)](CHNOS)·2HO (), [Ni(HO)](CHNOS)·2HO (), and [Co(HO)](CHNOS)·2HO (), are reported. These materials exhibit thermochromic properties, with a color change from red-bronze to grayish-red after the first step of their dehydration process completed around 80 °C (conversion of to [Cu(HO)(CHNOS) ()]), and then, this grayish-red color becomes lighter after the second step, which is completed around 230 °C (conversion of to [Cu(CHNOS)] ()).

Foreword to the AfCA collection: celebrating work published by African researchers in IUCr journals.

This virtual collection is a celebration. It is a celebration of crystallography in Africa, and a celebration of the international crystallography community. It commemorates the founding of the African Crystallographic Association (AfCA), which was accepted as the newest Regional Associate of the International Union of Crystallography (IUCr) in 2023, the year of the 75th anniversary of the first IUCr Congress and General Assembly.

Needle tract seeding following percutaneous biopsy of pediatric head and neck sarcoma: A case report.

This case report demonstrates the possibility of sarcoma biopsy needle track seeding from FNA/Core Needle Biopsy during the workup of a pediatric head and neck mass. Though not currently widely practiced in head and neck tumors, surgeons may consider placing biopsy tracks in the area of planned resection for suspected head and neck malignancies as is more common in approaches to extremity sarcoma.

Mechanically compliant single crystals of a stable organic radical.

Mechanically compliant organic crystals are the foundation of the development of future flexible, light-weight single-crystal electronics, and this requires reversibly deformable crystalline organic materials with permanent magnetism. Here, we report and characterize the first instance of a plastically bendable single crystal of a permanent organic radical, 4-(4'-cyano-2',3',4',5'-tetrafluorophenyl)-1,2,3,5-dithiadiazolyl. The weak interactions between the radicals render single crystals of the β phase of this material exceedingly soft, and the S-N interactions facilitate plastic bending.

The Impact of Dental Care in Head and Neck Cancer Outcomes: A Systematic Review and Meta-Analysis.

Objective/hypothesis: The objective of this study was to perform a systematic review and meta-analysis to determine the impact of dental care on head and neck (H&N) cancer survival.

Methods: A comprehensive literature search was performed using PubMed, MEDLINE, and CINAHL to find all relevant studies from the date of inception to March 2020. Systematic review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, and meta-analysis was performed using the random effects logistic regression model.

A Multistimulus Responsive Porous Coordination Polymer: Temperature-Mediated Control of Solid-State [2+2] Cycloaddition.

Either of two different isomeric products can be selectively obtained by photochemical [2+2] cycloaddition of 1,4-bis[2-(4-pyridyl)ethenyl]-benzene within a porous coordination polymer (PCP). The cycloaddition product obtained depends on the temperature at which irradiation occurs. A rare temperature-induced phase transition alters the conformation of the photoactive ligand in the PCP, and thereby the positions at which cycloaddition occurs.

Solvent-Mediated Synthesis of Cyclobutane Isomers in a Photoactive Cadmium(II) Porous Coordination Polymer.

Photochemical [2+2] cycloaddition of 1,4-bis[2-(4-pyridyl)ethenyl]benzene, carried out in a Cd porous coordination polymer (PCP), produces different isomeric products depending on the guest solvent present in the PCP during irradiation. The nature of the included guest influences the conformation of the ligand, and thus the outcome of the cycloaddition reaction. We demonstrate controlled production of the two isomers from the same PCP by simple exchange of solvent.

Inclusion of a dithiadiazolyl radical in a seemingly non-porous solid.

Inclusion of the dithiadiazolyl radical PhCNSSN˙ into the dynamically porous metallocycle [Cu(L1)Cl], where L1 is the bidentate ligand 1,3-bis(imidazol-1-ylmethyl)-2,4,6-trimethylbenzene, has been achieved by gas phase diffusion. Single crystal X-ray diffraction, powder X-ray diffraction, UV-visible spectroscopy, EPR and SQUID magnetometry studies confirm inclusion of the radical into this seemingly non-porous material, and illustrate the antiferromagnetic coupling between the paramagnetic host and guest species. The radical guest is readily released by heating or by the addition of solvent (CHCl).

Cobalt Porphyrin-Thiazyl Radical Coordination Polymers: Toward Metal-Organic Electronics.

Herein we delineate an unusual one-dimensional coordination polymer (CP), 3, prepared from S = 1/2 Co(TPP), 1 (TPP = 5,10,15,20-tetraphenylporphyrin dianion), and S = 1/2 4-(4'-pyridyl)-1,2,3,5-dithiadiazolyl (py-DTDA) radical, 2. The atypically long S-S distance for CP 3 (2.12 Å) reflects fractional electron transfer from the formally Co(II) ion into the antibonding π-SOMO of the metal-bound py-DTDA bridging ligand.

Interconversion between different stoichiometric forms of a three-component crystal via liquid-assisted grinding.

A second polymorphic form of a 1 : 2 : 3 pamoate : DABCO : water salt has been obtained by liquid-assisted grinding, and it is shown that interconversion between this salt and a salt with 1 : 1 : 2 stoichiometry is facile via liquid-assisted grinding with additional amounts of pamoic acid (to generate the 1 : 1 : 2 salt) or DABCO (to generate the 1 : 2 : 3 salt).

Porous salts based on the pamoate ion.

A number of porous salts based on the pamoate anion in combination with lutidinium or picolinium cations have been characterised. One salt undergoes single-crystal to single-crystal solvent exchange, while another isostructural series of salts contain channels that can be partly evacuated without collapse of the framework.

Inclusion of thiazyl radicals in porous crystalline materials.

The incorporation of benzodithiazolyl (BDTA) and methylbenzodithiazolyl (MBDTA) radicals into porous hybrid frameworks via gas phase diffusion revealed that inclusion appeared selective for the MIL53(Al) framework against a range of other potential hosts. Both PXRD and EPR studies are consistent with retention of a π*-π* dimer motif for BDTA in MIL53(Al)@BDTA whereas MBDTA in MIL53(Al)@MBDTA appears to be monomeric. The guests are readily released by the addition of solvent (CH(2)Cl(2)).

Human-impacted water resources: domain stratification and mapping to determine hydrologically similar units.

Geographic Information Systems (GIS) and multivariate statistical analyses were used to partition the United States into Human Influenced Water Environmental Classes (HIWECs) for the purpose of determining hydrologically similar units within the conterminous United States. Such a framework could be used to investigate various categories of watersheds throughout the country or to establish observatory sites in variant hydrologies. These HIWECs represent areas that are relatively homogeneous with respect to the human influence variables of land cover, population density, and water use; the climate variables of temperature and precipitation; and the physical variables of slope, bedrock permeability, and soil permeability.

Spectroscopic determination of temperature and density spatial profiles and mix in indirect-drive implosion cores.

In the field of inertial confinement fusion (ICF), work has been consistently progressing in the past decade toward a more fundamental understanding of the plasma conditions in ICF implosion cores. The research presented here represents a substantial evolution in the ability to diagnose plasma temperatures and densities, along with characteristics of mixing between fuel and shell materials. Mixing is a vital property to study and quantify, since it can significantly affect implosion quality.

Search for a predicted hydrogen bonding motif--a multidisciplinary investigation into the polymorphism of 3-azabicyclo[3.3.1]nonane-2,4-dione.

The predictions of the crystal structure of 3-azabicyclo[3.3.1]nonane-2,4-dione submitted in the 2001 international blind test of crystal structure prediction (CSP2001) led to the conclusion that crystal structures containing an alternative hydrogen bonded dimer motif were energetically competitive with the known catemer-based structure.

Achieving AOTA's Centennial Vision: The Role of the Educators-Viewpoint.

Utilizing the latest technology, improving our communication skills, celebrating diversity wherever we encounter it, and increasing our political activism are the keys to success for OT's next 100 years.

Screening for crystalline salts via mechanochemistry.

Neat grinding and solvent-drop grinding methods are found to be effective screening tools for indicating the potential for crystalline salt formation involving a given acid-base pair, as demonstrated with two model pharmaceuticals.

Crystal structures and magnetic properties of a sterically encumbered dithiadiazolyl radical, 2,4,6-(F3C)3C6H2CNSSN.

The sterically protected dithiadiazolyl radical (F3C)3C6H2CNSSN. (1) crystallises in two polymorphs: 1alpha, comprised of monomeric units and 1beta, containing a mixture of both pi*-pi* dimers and S = (1/2) monomers; whilst both polymorphs exhibit similar structure-directing motifs, the variation in packing leads to different magnetic behaviour.

Occurrence of pharmaceutically acceptable anions and cations in the Cambridge Structural Database.

The occurrence of a number of pharmaceutically acceptable counterions in the Cambridge Structural Database (CSD) has been investigated. The results have been compared to the occurrence of the same counterions in a list of known pharmaceutical salts. Chloride salts are by far the highest occurring in both groups.

Dependence of shell mix on feedthrough in direct drive inertial confinement fusion.

The mixing of cold, high-density shell plasma with the low-density, hot spot plasma by the Rayleigh-Taylor instability in inertial confinement fusion is experimentally shown to correlate with the calculated perturbation feedthrough from the ablation surface to the inner shell surface. A fourfold decrease in the density of shell material in the mix region of direct drive implosions of gas filled spherical plastic shells having predicted convergence ratios approximately 15 was observed when laser imprint levels were reduced and the initial shell was thicker, corresponding to a reduction in the feedthrough rms level by a factor of 6. Shell mix is also shown to limit the spherical compression of the implosion.

Small molecule fixation by a dithiadiazolyl radical: X-ray crystal structures of (CF3C6H3FCNSSN)2 and (CF3C6H3FCNSSN)2 x G (G = N2, Ar, CO2 and SO2).

The title dithiadiazolyl radical, F3CC6H3FCNSSN (1) forms inclusion structures with small molecules (such as N2, CO2, Ar and SO2) when sublimed under partial atmospheres of the guest.

Shell mix in the compressed core of spherical implosions.

The Rayleigh-Taylor instability in its highly nonlinear, turbulent stage causes atomic-scale mixing of the shell material with the fuel in the compressed core of inertial-confinement fusion targets. The density of shell material mixed into the outer core of direct-drive plastic-shell spherical-target implosions on the 60-beam, OMEGA laser system is estimated to be 3.4(+/-1.