Powder Diffraction Investigations Research Articles

Preparation and characterization of polymeric cross-linked hydrogel patch for topical delivery of gentamicin

Abstract This research aimed to prepare and characterize a new type of polymeric cross-linked topical hydrogel patches for the treatment of wound infections. The free radical polymerization method was used to prepare the topical hydrogel patches by utilizing natural polymers, i.e., agarose and gelatin. These natural polymers were chemically cross-linked with monomer (acrylic acid) using ammonium persulfate as an initiator via the cross-linker N,N methylene bisacrylamide. An antibiotic, i.e., gentamicin sulfate was loaded into a designed polymeric system. The polymeric cross-linked topical hydrogel patches were made in a spherical shape, which was revealed to be stable and elastic. Fourier transform infrared spectroscopy, scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, and X-ray powder diffraction investigation were used to characterize the topical hydrogel patches. Polymeric cross-linked hydrogel patches were evaluated for their sol–gel analysis, swelling studies, in vitro drug release studies against pH 5.5, 6.5, and 7.4, ex vivo drug permeation, and the deposition study on the rabbit’s skin by using a Franz diffusion cell. In addition, the skin irritation study and wound healing performance of drug-loaded topical patches were also assessed and compared to commercially available formulations. The topical hydrogel patches were found to be non-irritating to the skin for up to 72 h as determined by a Draize patch test and when compared to marketed formulations, these topical patches resulted in faster wound healing. The prepared formulation showed promising potential for the treatment of skin wound infection.

Synthesis of Green Cerium Oxide Nanoparticles Using Plant Waste from Colocasia esculenta for Seed Germination of Mung Bean (Vigna radiata)

Synthesis of cerium oxide (CeO2) nanoparticles (NPs) via biological approach has received a lot of interest to reduce the harmful effects of chemical synthesis. In the present study, Colocasia esculenta leaf extract facilitated the preparation of CeO2-NPs by using the sol-gel technique. The crystal structural of CeO2-NPs was proven by X-ray powder diffraction (XRD) investigation to be cubic with size of 2.94 nm according to Debye–Scherrer equation. As demonstrated in the transmission electron microscopy (TEM) image, CeO2-NPs have a spherical form with an average size of 2.04 nm which is almost consistent with a finding from XRD analysis. Energy dispersive X-ray (EDX) measurements exhibited high-intensity peaks attributed to Ce and oxygen and further proved the creation of CeO2-NPs. The Fourier transform infrared spectroscopy (FTIR) analysis revealed the presence of Ce-O stretching, indicating the formation of CeO2-NPs. Functional groups of O-H, C-O, and C=O peaks were found in a spectrum due to the phytochemical components that were responsible for reducing and stabilizing during the synthesis process of CeO2-NPs. The examined UV-visible spectra exhibited the absorbance peak at 213 nm. The synthesized NPs produced in this study were further investigated for mung bean seed germination, whereby the influence of grain germination and growth rate demonstrated the significant finding.

Rack-gear structures in columnar liquid crystal phases of trialkoxybenzyl pentafluorobenzoates and their influences on intercolumnar interdigitation and macroscopic morphologies

ABSTRACT In this study, 3,4,5-trialkoxybenzyl pentafluorbenzoates with alkyl chains of various lengths were synthesised, and the phase transition behaviours, liquid crystallinities, and molecular packing structures of their columnar phases were investigated. The results showed that discs comprising two half-discoid molecules stack up to form columns with rack-gear structures, generating columnar liquid crystal phases. From powder and single crystal X-ray diffraction investigation, the mechanism of the self-assembly of molecules into columns and their intercolumnar interdigitation was postulated. Furthermore, it was revealed that the combination of alkyl groups of the benzyl groups was closely related to the type of columnar liquid crystal phases generated and the macroscopic morphologies of the liquid crystal domains.

Al-Doped SrMoO3 Perovskites as Promising Anode Materials in Solid Oxide Fuel Cells.

Two perovskite materials with SrMo1−xAlxO3−δ (x = 0.1, 0.2) compositions have been synthesized by reduction from the corresponding scheelite phases, with SrMo1−xAlxO4−δ stoichiometry; the pertinent characterization shows that the defective perovskites can be used as anode materials in solid oxide fuel cells, providing maximum output power densities of 633 mW/cm2 for x = 0.2. To correlate structure and properties, a neutron powder diffraction investigation was carried out for both perovskite and scheelite phases. Both perovskites are cubic, defined in the Pm-3m space group, displaying a random distribution of Mo and Al cations over the 1a sites of the structure. The introduction of Al at Mo positions produced conspicuous amounts of oxygen vacancies in the perovskite, detected by neutrons. This is essential to induce ionic diffusion, providing a mixed ionic and electronic conduction (MIEC), since in MIEC electrodes, charge carriers are combined in one single phase and the ionic conductivity can be one order of magnitude higher than in a conventional material. The thermal expansion coefficients of the reduced and oxidized samples demonstrated that these materials perfectly match with the La0.8Sr0.2Ga0.83Mg0.17O3−δ electrolyte, La0.4Ce0.6O2−δ buffer layer and other components of the cell. Scanning electron microscopy after the test in a real solid oxide fuel cell showed a very dense electrolyte and porous electrodes, essential requirements for this type of fuel. SrMo1−xAlxO3−δ perovskites are, thus, a good replacement of conventional biphasic cermet anodes in solid oxide fuel cells.

Alkali activated slag cement doped with Zn-rich electric arc furnace dust

Steel production in electric arc furnaces yielding formation of two waste materials, toxic electric arc furnace dust (EAFD) and non-hazardous electric arc furnace slag (EAFS). EAFD presents a potential hazard to the environment as it is characterized by the presence of heavy metals. This study dealt with the synthesis and characterization of alkali activated slag cement (AAS) based on EAFS with addition of 1-7% of Zn-rich EAFD dopant. Effects of slag replacement with dust on the compressive strength, physico-chemical, mineralogical and morphological properties of AAS cement were evaluated. This replacement lead to the development of porosity of AAS matrix, and retardation of slag alkali activation which resulted in the weakening of the AAS structure and hence in compressive strength decrease as pure AAS cement compressive strength was 21.04 MPa while AAS doped with 7% of EAFD reached only 8.4 MPa. On the other hand, AAS doped with 5% of EAFD exhibited compressive strength of 13.82 MPa, making it is still suitable for construction purposes... Scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM/EDS), scanning transmission electron microscope (STEM) in high angle annular dark field (HAADF) mode, X-ray powder diffraction (XRPD) investigations and standard EN 12457-2 leaching test provided information on the ability of AAS based on EAFS to fix Zn in AAS matrix.. The concentration of Zn in leachate of AAS cement doped with 5% of EAFD was 9.20 mg/kg which is below the limit prescribed for the granular waste acceptable at non-hazardous landfills according the European Directive 2003/33/CE.

Role of "Dumbbell" Pairs of Fe in Spin Alignments and Negative Thermal Expansion of Lu2Fe17-Based Intermetallic Compounds.

Knowledge of negative thermal expansion (NTE) is an interesting issue in the field of materials science and engineering. It has been proposed that the unique dumbbell pairs of Fe (dumbbells) are highly entangled in the NTE behaviors of R2Fe17 (R = rare earth) compounds but still remain controversial. Here, a facile method is employed to explore the role of dumbbells in spin alignments and NTE by the nonstoichiometric design of Lu2-xFe17 compounds. The powder synchrotron X-ray diffraction, magnetometry, and neutron powder diffraction investigations indicate that a decrease of the Lu content can enhance the dumbbell concentration and motivate an incommensurate magnetic structure simultaneously. However, increasing the dumbbell concentration makes little difference in the amplitude of the ordered magnetic moments of Fe sublattices, which reveals an equivalent NTE behavior for Lu2-xFe17 compounds. This work gives insight into the role that dumbbells played in spin alignments and NTE for Lu2Fe17-based compounds, correcting the previously proposed conjecture and probably conducive to adjusting the related magnetic performances of R2Fe17 compounds in the future.

Photocatalytic and Electrocatalytic Properties of NGr-ZnO Hybrid Materials.

N-doped graphene-ZnO hybrid materials with different N-doped graphene:ZnO wt% ratios (1:10; 1:20; 1:30) were prepared by a simple and inexpensive sol-gel method. The materials denoted NGr-ZnO-1 (1:10), NGr-ZnO-2 (1:20), and NGr-ZnO-3 (1:30) were investigated with advanced techniques and their morpho-structural, photocatalytic, and electrocatalytic properties were reported. Hence, pure N-doped graphene sample contains flakes with the size ranging from hundreds of nanometers to micrometers. In the case of all NGr-ZnO hybrid materials, the flakes appear heavily decorated with ZnO nanoparticles, having a cauliflower-like morphology. The X-ray powder diffraction (XRD) investigation of N-doped graphene sample revealed that it was formed by a mixture of graphene oxide, few-and multi-layer graphene. After the ZnO nanoparticles were attached to graphene, major diffraction peaks corresponding to crystalline planes of ZnO were seen. The qualitative and quantitative compositions of the samples were further evidenced by X-ray photoelectron spectroscopy (XPS). In addition, UV photoelectron spectroscopy (UPS) spectra allowed the determination of the ionization energy and valence band maxima. The energy band alignment of the hybrid materials was established by combining UV–Vis with UPS results. A high photocatalytic activity of NGr-ZnO samples against rhodamine B solution was observed. The associated reactive oxygen species (ROS) generation was monitored by electron paramagnetic resonance (EPR)-spin trapping technique. In accordance with bands alignment and identification of radical species, the photocatalytic mechanism was elucidated.

Manipulating Spin Alignments of (Y,Lu)1.7Fe17 Intermetallic Compounds via Unusual Thermal Pressure.

External pressure has been successfully employed to achieve desirable spin alignments in the field of materials science but is seriously restricted by the difficulty of reaching high pressure with conventional methods. The search for simple and effective ways to apply pressure on the lattice is challenging but intriguing. Here we report a new strategy to manipulate the spin alignments of (Y,Lu)1.7Fe17 intermetallic compounds through unusual thermal pressure. The spin alignments of Fe initially lie parallel inside the basal plane and then turn spirally between adjacent layers with a zone axis along the c direction under higher Lu concentration. The synchrotron and neutron powder diffraction investigations clearly reveal that the direction of spin alignments is highly correlated to large lattice contraction induced by negative thermal expansion (NTE), an unusual thermal pressure, along the c direction. The critical lattice parameter c to form spiral spin alignments is determined unambiguously. This work presents a feasible way to adjust spin alignments through NTE, which might be conducive to the future design of particular spin alignments instead of physical pressure for functional magnetic materials.

Water Availability and Deformation Processes in Smectite‐Rich Gouges During Seismic Slip

AbstractSmectite clays occur in subduction zone fault cores at shallow depth (approximately 1 km; e.g., Japan Trench) and landslide décollements (e.g., Vajont, Italy, 1963). The availability of pore fluids affects the likelihood that seismic slip propagates from deeper to shallow fault depths or that a landslide accelerates to its final collapse. To investigate the deformation processes active during seismic faulting we performed friction experiments with a rotary machine on 2‐mm‐thick smectite‐rich gouge layers (70/30 wt % Ca‐montmorillonite/opal) sheared at 5‐MPa normal stress, at slip rates of 0.001, 0.01, 0.1, and 1.3 m/s, and total displacement of 3 m. Experiments were performed on predried gouges under vacuum, under room humidity and under partly saturated conditions. The fault shear strength measured in the experiments was included in a one‐dimensional numerical model incorporating frictional heating, thermal, and thermochemical pressurization. Quantitative X‐ray powder diffraction and scanning electron microscopy investigations were performed on pristine and deformed smectite‐rich gouges. Under dry conditions, cataclasis and amorphization dominated at slip rates of 0.001–0.1 m/s, whereas grain size sensitive flow and, under vacuum, frictional melting occurred at fast slip rates (1.3 m/s). Under partly saturated conditions, frictional slip in a smectite foliation occurred in combination with pressurization of water by shear‐enhanced compaction and, for V = 0.01–1.3 m/s, with thermal pressurization. Pseudotachylytes, the only reliable microstructural markers for seismic slip, formed only with large frictional power (>2 MW/m2), which could be achieved at shallow depth with high slip rates, or, at depth, with high shear stress in dehydrated smectites.

Soft-to-hard consecutive templating one-pot route from metal nitrate/phenol resin/surfactant to mesoporous metal oxides with enhanced thermal stability

Abstract Mesoporous materials with crystalline ZrO2, Y2O3, and CeO2 frameworks were one-pot synthesized from a clear solution of ethanol containing metal nitrates, organic surfactant (i.e., Pluronic® F-127), formaldehyde, and phloroglucinol. The solution was converted to a mesostructured nanocomposite of metal nitrate/phenol resin/surfactant via a solvent evaporation-induced self-assembly process. The obtained nanocomposite was calcined at 800 °C in a N2 atmosphere. X-ray powder diffraction and electron microscopic investigation revealed that the calcination caused amorphous-to-crystalline transformations in the metal oxide frameworks, while sintering to bulk metal oxides was prevented by the in-situ generated carbon component. Mesoporous metal oxides with a crystalline framework were obtained when the carbon skeleton was burnt off. The mesoporous metal oxides exhibited high BET surface areas, narrow pore-size distributions, and enhanced thermal stability. A practical benefit of the mesoporous metal oxides was demonstrated with Au/CeO2 exhibiting high catalytic activity in the water-gas-shift reaction.

Structural and magnetic properties of the Yb2Pd2(In1−xSnx) system: a synchrotron x-ray and neutron powder diffraction investigation

The structural properties of the Yb2Pd2(In1−xSnx) system were investigated at room temperature by synchrotron x-ray powder diffraction. All the inspected compositions (x = 0.0, 0.3, 0.4, 0.5, 0.6, 0.8, 0.9) crystallize in the tetragonal space group P4/mbm; the cell parameters exhibit a non-linear dependence on composition, whereas cell volume changes more regularly, with a minimum at x = 0.8.Samples with Sn content x = 0.5, 0.6, 0.9 were also analysed by neutron diffraction down to 0.5 K. No evidence for a structural transition can be detected at low temperature, whereas an antiferromagnetic ordering is observed, characterized by a propagation vectors k = (0,0,½). Magnetic moments order in the tetragonal ab-plane and the magnetic structure belongs to the Shubnikov magnetic space group P4/mbm.

Hydrogen Evolution Reaction in an Alkaline Solution via ε-Fe3N Phase Formation on AISI 316 Stainless Steel by Plasma Treatment

Surface modification techniques can be used to enhance the use of low-cost materials in water electrolysis applications, improving their hydrogen evolution efficiency and life. In this work, a well-known AISI 316 stainless steel was treated with nitrogen direct current glow discharge plasma for the periods of 2, 3, 4, and 5 hours. The e-Fe3N phase was created from the first plasma treatment period, as detected by the X-ray powder diffraction and X-ray photo-electron spectroscopy investigations. To understand the effect of the e-Fe3N phase formation and growth on the hydrogen evolution rate and mechanism both the electrochemical and electro-chemical impedance spectroscopy measurements were done. Advanced plasma treatment over time and enhanced e-Fe3N phase growth were found to decrease the Tafel slope, over-potential, and polarization resistance, which contributes to improving the hydrogen evolution reaction properties of AISI 316 stainless steel. A lab scale electrolyzer equipped with a distilled water displacement attachment was prepared to evaluate the HER practically. The contact angle was measured to find an evidence on the effect of the advanced plasma treatment on the surface hydrophilicity.

Effect of Methyl-β-Cyclodextrin on the antimicrobial activity of a new series of poorly water-soluble benzothiazoles

The antibacterial activity of the S-unsubstituted- and S-benzyl-substituted-2-mercapto-benzothiazoles 1-4 has been evaluated after complexation with Methyl-β-Cyclodextrin (Me-β-CD) or incorporation in solid dispersions based on Pluronic® F-127 and compared with that of the pure compounds. This with the aim to gain further insights on the possible mechanism(s) involved in the CD-mediated enhancement of antimicrobial effectiveness, a promising methodology to overcome the microbial resistance issue. Together with Differential Scanning Calorimetry, FT-IR spectroscopy and X-ray Powder Diffraction investigations, a molecular modeling study focused on compounds 2 and 4 showed that the S-unsubstituted compound 2/Me-β-CD complex should be more stable than S-benzyl-substituted 4/Me-β-CD. Only for 1/Me-β-CD or, particularly, 2/Me-β-CD complexes, the antibacterial effectiveness was enhanced in the presence of selected bacterial strains. The results herein presented support the mechanisms focusing on the interactions of the bacterial membrane with CD complexes more than those focusing on the improvement of dissolution properties consequent to CD complexation.

Structure, vibrational, electrical and optical study of [C2H10N2] (IO3)2·4HIO3

The iodate salt [C2H10N2](IO3)2·4HIO3 denoted as EBITIA, was synthesized at this first time by A. M. Petrosyan et al. during the investigation the system C2H8N2HIO3H2O. In their study authors, have characterized the compound using iodometric titration and IR spectroscopy to determine its stocheometric composition. Later, K. Saidi et al. have studied the structural properties of the EBITIA crystal using X-ray single crystal diffraction at room temperature. In this work, this iodate salt was reproduced and was analyzed using the X-ray powder diffraction showing that the crystal structure of this compound corresponds well to the structrural model of the EBITIA. Variable temperature X-ray powder diffraction (VT-XRPD), 13C NMR, DSC and complex impedance spectroscopy (CIS) investigation were undertaken and show that the EBITIA is stable at the temperature range 303–393 K. The temperature dependence of both bulk and DC conductivities follow the Arrhenius law and the impedance data were fitted to an adequate equivalent circuit model consisting of a parallel combination of a bulk resistance and CPE. The near values of activation energies obtained from the conductivity and impedance measurements suggested that the electrical conductivity in the EBITIA may be due to the ion hopping mechanism.Moreover, the DFT calculation of the optimized geometries, vibrational wavenumbers, FOM's and Mulliken charge were also reported and were in better agreement with experiments. The complete, precise and reliable assignments of the fundamental vibrational modes were performed with the aid of potential energy distribution (PED). The optical properties of the compound were also studied using diffuse reflectance (DRS) and fluorescence spectroscopy.

Exploration of Phase Compositions, Crystal Structures, and Electrochemical Properties of NaxFeyMn1–yO2 Sodium Ion Battery Materials

Layered manganese oxide materials are widely used in sodium and lithium ion batteries, but significant discrepancies are encountered in the literature with respect to their electrochemical properties. This could be due to difficulties in establishing the exact phase compositions and crystal structures (typically P2, P3, O2, and O3, their distorted analogues, e.g., P’2, hydrated - PH2, or carbonated - PC2, phases) of a given synthesis product, especially when only crude crystallographic indexing is used without structural analysis. Here we report a benchmark high-resolution synchrotron powder diffraction investigation of a broad composition range of the layered NaxFeyMn1–yO2 cathode materials (x = 0.5, 0.7, and 1.0 and y = 0.3, 0.5, and 0.7) with respect to phase composition, crystal structure, and electrochemical properties. On the basis of multiphase Rietveld refinements, it is shown that crystal structure can be controlled to a certain degree for different x and y. Most synthesis products contain a comp...

Coexistence of magnetic phases in La(Mn0.70Ga0.30)O3 under high pressure: A neutron powder diffraction investigation

Neutron powder diffraction was used to analyse the La(Mn0.70Ga0.30)O3 compound under pressures of up to 6.1 GPa and temperatures down to 1.3 K. At ambient pressure, the magnetic ground state corresponds to a canted antiferromagnetic AxFy-type spin ordering. As the pressure increases, the Fy component is suppressed and a novel Ay-type ordering takes place coexisting with the Ax-type.The simultaneous occurrence of these spin orderings can be ascribed to a demixing of the pristine nuclear phase into a Jahn-Teller distorted phase (where the Ax-ordering takes place) and an undistorted nuclear phase which grows under pressure (where the Ay-ordering develops).

A high-resolution neutron powder diffraction study of the low-temperature structural phase transitions in RbCaF3 perovskite

The temperature dependence of the crystal structure and thermoelastic properties of RbCaF3 perovskite are reported from a high-resolution neutron powder diffraction investigation in the temperature interval 2–300 K. Two phase transitions have been identified from these data, the first from space group Pm3¯m to I4/mcm, at 200 K, has been well characterized in earlier studies, the second, from space group to I4/mcm to Pbnm has previously been less well understood. New results from the former transition show the order parameter evolves with a critical exponent of 0.284(5), and the phase is characterized by an Einstein temperature of 192(8) K, and a Debye temperature of 270(10) K. The temperature variation of the tetragonal spontaneous strain in this phase is consistent with an additional fourth order invariant in the Landau potential. The second phase transition is found to be strongly first order and a temperature dependent, and heating rate/cooling rate dependent phase coexistence is found at all temperatures below ~ 80 K on heating, and ~ 65 K on cooling. The evolution of the orthorhombic unit cell is atypical in the region of the phase transition, with a and b exhibiting strong negative linear thermal expansion, whilst the c axis behaves in the expected manner. The crystal structure of the Pbnm phase at 2 K is reported from an unconstrained Rietveld refinement for the first time.

KH2PO4 single crystals activated with the Ti4+ ions in the form of TiO2−x × nH2O nanoparticles: Structural peculiarities, point defects, and dielectric properties

Potassium dihydrogen phosphate KH2PO4 (KDP) single crystals activated with Ti4+ ions in the form of TiO2−x × nH2O nanoparticles in the η-phase, synthesized by the sulfate method using TiOSO4 × хH2SO4 × yH2O, have been first grown by the temperature lowering method and cut from pyramidal (P) and prismatic (Pr) growth sectors. The first-performed neutron powder diffraction investigation of P and Pr samples cut from the KDP:Ti4+ crystal allowed us to reveal vacancies in the K and H sites for both samples, their number being larger in the Pr structure compared to the P one. Taking into account the deficiency of the K and H sites, full occupation of the O site, presence of Ti4+ ions in the structure, and the electroneutrality condition, a partial substitution of (PO4)3− anion by the (SO4)2− one, larger for the Pr sample, was observed. The real compositions of P and Pr samples, correlated with the cation-anion internuclear distances, were refined. The dielectric permittivity of the Pr sample was significantly lower than that of the P one; it decreases with decreasing К–O, P–O, and O···H distances and increasing deficiency of the K and H sites.

In situ formation of surface-functionalized ionic calcium carbonate nanoparticles with liquid-like behaviours and their electrical properties.

This paper reports a new route to synthesize calcium carbonate (CaCO3)-based nanoscale ionic materials (NIMs) via an in situ formation method to form the CaCO3 nanoparticles with a polysiloxane quaternary ammonium salt (PQAC) corona (PQAC-CaCO3 nanoparticles), followed by an ionic exchange reaction to fabricate a poly(ethylene glycol)-tailed sulfonate anion (NPEP) canopy. The chemical compositions and structures of the CaCO3-based NIMs synthesized in this work were confirmed by Fourier-transform infrared spectroscopy and solid-state 13C NMR spectroscopy. Transmission electron microscopic observation indicated that the CaCO3-based NIMs presented a rhombohedral shape with a well-defined core-shell structure, and they also obtained an NPEP canopy with a thickness of 4–6 nm. X-ray powder diffraction investigation confirmed that the CaCO3 inner core had a calcite crystalline structure, whereas the NPEP canopy was amorphous. The NPEP canopy was found to show a characteristic crystallization–melting behaviour in the presence of the ion bonding with PQAC-CaCO3 nanoparticles according to the characterization of differential scanning calorimetry. Thermogravimetric analysis indicated that the CaCO3-based NIMs achieved a high content of NPEP canopy as well as an improvement in thermal stability owing to the ion-bonding effect. Most of all, the CaCO3-based NIMs demonstrated a liquid-like behaviour above the critical temperature in the absence of solvent. Moreover, the CaCO3-based NIMs also showed a relatively high electrical conductivity with a temperature dependency due to the ionic conductive effect. This work will provide a more feasible and energy-saving methodology for the preparation of CaCO3-based NIMs to promote their industrialization and extensive applications.

Synthesis, Crystal Structures, and Properties of M(NCS)2‐3‐aminomethylpyridine Coordination Compounds (M = Cd, Zn)

Reaction of Cd(NCS)2 or Zn(NCS)2 with 3‐aminomethylpyridine (3‐AMPy) leads to the formation of five compounds with the compositions [Cd(NCS)2(3‐AMPy)2·(3‐AMPy)]n (1‐Cd), [M(NCS)2(3‐AMPy)2]n [M = Cd (2‐Cd), Zn (2‐Zn)] [Cd(NCS)2(3‐AMPy)]n (3‐Cd), and [Zn(NCS)2(3‐AMPy)]2 (3‐Zn). In 1‐Cd the Cd cations are linked by the 3‐AMPy ligands into layers that consist of rings, built up of four Cd cations and four 3‐AMPy ligands. These layers are stacked to form channels, in which the 3‐AMPy solvate molecules are located. In the isotypic compounds 2‐Cd and 2‐Zn the metal cations are also linked into layers by the 3‐AMPy ligands with an identical layer topology as that in 1‐Cd, but a completely different conformation of the 3‐AMPy ligand. In the most 3‐AMPy deficient compound 3‐Cd, the Cd cations are linked by μ‐1,3‐bridging thiocyanate anions and 3‐AMPy ligands into chains, that are further connected into layers by additional anionic ligands. In 3‐Zn two Zn cations are linked by pairs of 3‐AMPy ligands into discrete dimers. Thermoanalysis and X‐ray powder diffraction (XRPD) investigations show that upon heating 1‐Cd transforms into 2‐Cd and 2‐Zn into 3‐Zn. The compounds 2‐Cd, 3‐Cd, 2‐Zn, and 3‐Zn present ligand‐based luminescence in the blue‐green spectral range with maxima between 21276 and 21795 cm–1.