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The computational simulations for electronic properties of cadmium (Cd) coordinated L-alanine NDI ligand (H2-l-ala NDI) based complex are the focus of this research. For the first time, the Cd-NDI complex (monomer) has been produced using water as the solvent; this is a new approach to synthesizing the Cd-NDI complex that has not been reported yet. Along with crystallography and Hirsch field analysis, CAM-B3LYP/LANL2DZ and B3LYP/LANL2MB basis sets were used, and in-depth characterisation of the Cd-NDI complex by following DFT and TD-DFT hypothetical simulations. Hyperpolarizabilities, frontier molecular orbitals (FMOs), the density of states (DOS), dipole moment (µ), electron density distribution map (EDDM), transition density matrix (TDM), molecular electrostatic potential (MEP), electron-hole analysis (EHA), and electrical conductivity (σ) have all been studied regarding the Cd-NDI complex. The vibrational frequencies and types of interaction are studied using infrared (IR) and non-covalent interaction (NCI) analysis with iso-surface. In comparison to the Cd-NDI complex with 2.61, 2.42 eV Eg (using CAM-B3LYP/LANL2DZ and B3LYP/LANL2MB basis sets, respectively) and 376 nm λmax, (in case of B3LYP/LANL2MB λmax is higher), H2-l-ala NDI have 3.387 eV Eg and 375 nm λmax, metal-ligand coordination in complex dramatically altered charge transfer properties, such as narrowing band gap (Eg). Based on the electronic properties analysis of Cd-NDI complex, it is predicted that the Cd-NDI complex will have a spectacular (nonlinear optical) NLO response. The Cd-NDI complex is discovered to be advantageous for the creation of future nanoscale devices due to the harmony between the Cd metal and H2-l-ala NDI, in addition to their influences on NLO characteristics.

Single crystals of (Pb 0.86 Sr 0.14 ) 5 Ge 3 O 11 are prepared by a slow melt cooling. The effect of high-energy electron irradiation with fluences up to 6.2·10 18  e/cm 2 on the structural and dielectric properties of these crystals is studied; the dependence of crystal structure parameters on the fluences is considered; the structural mechanism of selective substitution of Pb by Sr is established. It is determined that the sites occupied by lead with a lone pair are not substituted by strontium cations. Up to the fluences of 6.2·10 18  e/cm 2 , the (Pb 0.86 Sr 0.14 ) 5 Ge 3 O 11 structure remains perfect. It is shown that the irradiation with these fluences preserves the paraelectric structure at 293 K ( space group) and causes only minor atomic displacements. The temperature dependences of the dielectric permittivity and the dielectric loss (in the ranges of 5-300 K and 1-1000 kHz) show that the irradiation shifts T C from 158 K to 145 K and increases the diffusion of the ferroelectric phase transition.

Zn(OAc) 2 (H 2 DEA) was synthesized by the reaction of zinc acetate dihydrate (Zn(OAc) 2 •2H 2 O) with diethanolamine (H 2 DEA), and was characterized using single-crystal X-ray structural analysis, nuclear magnetic resonance spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, and elemental analysis. Zn(OAc) 2 (H 2 DEA) had a trigonal bipyramidal geometry comprised of one zinc atom, two acetate groups, and one H 2 DEA as a neutral tridentate ligand to form two five-membered rings. The states of Zn(OAc) 2 (H 2 DEA) heated at various temperatures were determined by FT-IR spectroscopy. At 270 °C, the H 2 DEA ligand dissociated and was removed. The absorption bands assigned to Zn–O stretching vibration of Zn 4 O core such as the zinc-oxo cluster appeared. When heated at 500 °C, the absorption bands of μ 4 -oxozincate and the acetate group disappeared completely and hexagonal wurtzite structural ZnO was formed at 550 °C. A possible thermal decomposition pathway from Zn(OAc) 2 (H 2 DEA) to ZnO was proposed. The ZnO film was highly transparent and formed by the deposition of ZnO nanoparticles with size ~40 nm. Zn(OAc) 2 (H 2 DEA) was synthesized and characterized. The states of Zn(OAc) 2 (H 2 DEA) heated at various temperatures were determined by FT-IR spectroscopy, and the formation mechanism of ZnO was estimated. Highlights Zinc–diethanolamine complex was synthesized by the reaction of zinc acetate with diethanolamine. Zinc–diethanolamine complex was isolated and characterized. The formation mechanism of ZnO was estimated by FT-IR spectra.

AbstractPerfect stoichiometric Pb5Ge3O11 single crystals are irradiated with 60Co γ-rays (1·106 Rad) and high-energy electrons (0.13 e/cm2, 0.89 e/cm2, 2.18 e/cm2, 3.07·1018 e/cm2) at the Karpov Institute of Physical Chemistry. Changes in the structural and ferroelectric properties of the crystals are traced depending on the irradiation type and dose. Dielectric spectroscopy and second harmonic generation of laser radiation are used to determine the ferroelectric phase transition temperature TС. X-ray diffraction experiments are carried out on a Bruker D8 QUEST diffractometer with a PHOTON-II detector (MoKα radiation, 295 K). Based on the experimental structural amplitudes the crystal structures of the crystals before and after irradiation are solved and refined. Structural characteristics of the non-irradiated crystal are consistent with the previously reported data at the achieved significant improvement of their accuracy (R(F > 2σ(F)) = 0.028). Despite radiation defects introduced, Pb5Ge3O11 single crystals retain the crystal structure and ferroelectric properties. It is shown that irradiation performed maintains the polar structure at 295 K and causes changes in atomic displacements of separate atoms. It is supposed that a radiation-induced change in the Pb5Ge3O11 structure is of the high-temperature type and forms a new structural state close to a high-temperature modification of a non-irradiated Pb5Ge3O11 crystal. Irradiation leads to a gradual decrease in distortions and structure symmetrization. It is important that the kinetics and final products of these processes appreciably differ from those observed only upon thermal impacts. Polar shifts are calculated, and their dependence on the irradiation dose indicates a tendency to a decrease in polar shifts in lead germanate ferroelectric during irradiation.

Stoichiometric single crystals of Pb 5 (Ge 1– х Si x ) 3 O 11 solid solutions (0 ≤  x  ≤ 0.55) are obtained by slow cooling of 5PbO·3(1– y )GeO 2 ·3 y SiO 2 melts. The chemical analysis confirms their cation and anion stoichiometry. The effect of their high-energy (10 MeV) electron irradiation with fluences from 0.1·10 18  e/cm 2 to 4.39·10 18  e/cm 2 on the structural, ferroelectric, and nonlinear optical characteristics of the crystals is studied for the first time. The dependence of crystals on concentrations and fluences is detected. According to the date of dielectric spectroscopy and second harmonic generation of laser radiation, the doping with Si causes a systematic shift of T c to low temperatures, a decrease in the peak value of the dielectric permittivity, and a noticeable phase transition smearing with transforming to the zelaxor ferrollectric state of x  = 0.35. According to the structural studies of initial and irradiared, Pb 5 (Ge 1– x Si x ) 3 O 11 crystals, they retain the structural perfectness without any signs of amorphization. Structural distortions of Pb 5 (Ge 1– x Si x ) 3 O 11 do not significantly depend on the fluence.

In this work X-ray single crystal structural analysis was carried out on the clathrate hydrate of tetraisoamylammonium propionate with the composition (i-C5H11)4NC2H5CO2·36H2O. The hydrate was found to have an orthorhombic structure in space group Cmc21 with unit cell parameters: a = 21.281(2) Å, b= 12.010(7) Å, c = 24.768(3) Å (150 K). X-ray powder diffraction studies were performed of the hydrate phase, crystallized in the water–(i-C5H11)4NC2H5CO2 system in the concentration range of the salt (10–25 wt%) that is the crystallization region of the studied polyhydrate, according to the phase equilibria data. It was found, that in the given concentration region the same hydrate of orthorhombic structure is formed, unit cell parameters, obtained at 20 °C: a = 21.454(13) Å, b = 12.156(4) Å, c = 25.030(14) Å, are in a good agreement with the data of single crystal structural analysis.

Crystals of the ammonium (2.2.2‐cryptand) thiocyanate monohydrate complex, [NH4(2.2.2‐Crypt)]+ × SCN- · H2O, were studied by X‐ray structural analysis: space group P2/c, a = 11.303(2)*angst;, b = 8.313(1)Å, c = 14.392(3)Å, β = 110.39(2)°, Z = 2, 3680 independent measured reflections, R = 0.064. This complex is of the guest–host type: the cryptand ligand cavity contains the NH4+ cation with statistically disordered H atoms forming H bonds with each of its O and N heteroatoms. The SCN- anions and H2O molecules are linked by H bonds to form chains that are infinite along the z axis.

Crystals of the ionic complex (salt) of 4,7,13,16,21,24‐hexaoxa‐ 1,10‐diazabicyclo[8.8.8]hexacozane perchlorate, [H2(Crypt‐2.2.2)]2+ · 2ClO4-, were synthesized and studied by X‐ray structural analysis: space group C2/c, a = 20.198(3)Å, b = 10.119(2)Å, c = 12.938(2)Å, β = 90.97(1)°, Z = 4, 3030 measured independent reflections, R = 0.067. In these crystals, all atoms of the 2.2.2 dication are disordered over two positions with occupancies of 0.518(4) and 0.482(4). Two conformations of the disordered 2.2.2 dication are such that two H atoms at two nodal N atoms point to its cavity.

Architected materials that consist of periodic arrangements of nodes and struts are lightweight and can exhibit combinations of properties (such as negative Poisson ratios) that do not occur in conventional solids. Architected materials reported previously are usually constructed from identical ‘unit cells’ arranged so that they all have the same orientation. As a result, when loaded beyond the yield point, localized bands of high stress emerge, causing catastrophic collapse of the mechanical strength of the material. This ‘post-yielding collapse’ is analogous to the rapid decreases in stress associated with dislocation slip in metallic single crystals. Here we use the hardening mechanisms found in crystalline materials to develop architected materials that are robust and damage-tolerant, by mimicking the microscale structure of crystalline materials—such as grain boundaries, precipitates and phases. The crystal-inspired mesoscale structures  in our architected materials are as important for their mechanical properties as are crystallographic microstructures in metallic alloys. Our approach combines the hardening principles of metallurgy and architected materials, enabling the design of materials with desired properties. Inspired by the enhanced mechanical strength of microstructured metals, damage-tolerant architected materials are developed in which the internal structure is granular, with different regions having different lattice orientations.

Covalent organic framework (COF) materials have been difficult to characterize structurally and to exploit because they tend to form powders or amorphous materials. Ma et al. studied a variety of three-dimensional COFs based on imine linkages (see the Perspective by Navarro). They found that the addition of aniline inhibited nucleation and allowed the growth of crystals large enough for single-crystal x-ray diffraction studies. Evans et al. describe a two-step process in which nanoscale seeds of boronate ester–linked two-dimensional COFs can be grown into micrometer-scale single crystals by using a solvent that suppresses the nucleation of additional nanoparticles. Transient absorption spectroscopy revealed superior charge transport in these crystallites compared with that observed in conventional powders. Science , this issue p. 48 , p. 52 ; see also p. 35 The addition of aniline enables the growth of single crystals of imine-based covalent organic framework materials. The crystallization problem is an outstanding challenge in the chemistry of porous covalent organic frameworks (COFs). Their structural characterization has been limited to modeling and solutions based on powder x-ray or electron diffraction data. Single crystals of COFs amenable to x-ray diffraction characterization have not been reported. Here, we developed a general procedure to grow large single crystals of three-dimensional imine-based COFs (COF-300, hydrated form of COF-300, COF-303, LZU-79, and LZU-111). The high quality of the crystals allowed collection of single-crystal x-ray diffraction data of up to 0.83-angstrom resolution, leading to unambiguous solution and precise anisotropic refinement. Characteristics such as degree of interpenetration, arrangement of water guests, the reversed imine connectivity, linker disorder, and uncommon topology were deciphered with atomic precision—aspects impossible to determine without single crystals.