We present a versatile method to generate asymmetric profiles and use it to create Gaussian-like, Cauchy-like, and Pseudo-Voigt-like profiles in terms of elementary functions. Furthermore, this method guarantees that the position and magnitude of the global maximum are independent of the asymmetry parameter, which substantially facilitates the convergence of an optimizer when fitting the peaks to real data. This investigation shows that the method developed here exhibits favorable practical properties and is particularly well suited for various applications where asymmetric peak profiles are observed. For example, in X-ray diffraction (XRD) measurements, the use of asymmetric profiles is essential for obtaining accurate outcomes. This is because diffractometers can introduce asymmetry into the diffraction peaks due to factors such as axial divergence in the beam path. By taking this asymmetry into account during the modeling process, the resulting data obtained can be corrected for instrumental effects. The results of the study show that the evaluation of XRD using nearly defect-free LaB6 allows a precise characterization of the peak broadening caused by the diffractometer itself. Additional size-strain effects of ZnO are determined by considering the asymmetric peak profile of the diffractometer.

In the present study, we have discovered and identified a new crystalline form of pinaverium bromide, pinaverium bromide dihydrate (C26H41BrNO4⋅Br⋅2H2O), whose single crystals can be obtained by recrystallization from a mixture of water and acetonitrile at room temperature. The obtained crystals were characterized by X-ray single-crystal diffraction, and their crystal structure was also solved based on X-ray single-crystal diffraction data. The results show that the final pinaverium bromide dihydrate model contains an asymmetric unit of one pinaverium bromide (C26H41Br2NO4) molecule and two water molecules that combine with the bromine ion through O–H⋯O and O–H⋯Br hydrogen bonds. Then, the adjacent pinaverium bromide dihydrates are linked by O–H⋯O, O–H⋯Br, and C–H⋯O hydrogen bonds. On the other hand, the experimentally obtained X-ray powder diffraction pattern is in good agreement with the simulated diffraction pattern from their single-crystal data, confirming the correctness of the crystal structure. Hirshfeld surface analysis was employed to understand and visualize the packing patterns, indicating that the H⋯H interaction is the main acting force in the crystal stacking of pinaverium bromide dihydrate.

The crystal structure of cariprazine dihydrochloride has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional theory techniques. Cariprazine dihydrochloride crystallizes in space group P21/n (#14) with a = 27.26430(14), b = 7.29241(1), c = 12.80879(4) Å, β = 99.5963(2)°, V = 2511.038(8) Å3, and Z = 4 at 295 K. The crystal structure consists of layers of cations parallel to the bc-plane. The cations stack along the b-axis. Each H atom on the two protonated N atoms participates in a discrete N–H⋯Cl hydrogen bond. One Cl anion acts as an acceptor in two of these bonds, while the other Cl is an acceptor in only one bond. The result is to link the cations and anions into columns parallel to the b-axis. The powder pattern has been submitted to the ICDD for inclusion in the Powder Diffraction File™ (PDF®).

We present a simple analytical formalism based on the Lorentz-Scherrer equation and Bernoulli statistics for estimating the fraction of crystallites (and the associated uncertainty parameters) contributing to all finite Bragg peaks of a typical powder pattern obtained from a static polycrystalline sample. We test and validate this formalism using numerical simulations, and show that they can be applied to experiments using monochromatic or polychromatic (pink-beam) radiation. Our results show that enhancing the sampling efficiency of a given powder diffraction experiment for such samples requires optimizing the sum of the multiplicities of reflections included in the pattern along with the wavelength used in acquiring the pattern. Utilizing these equations in planning powder diffraction experiments for sampling efficiency is also discussed.

The crystal structure of benserazide hydrochloride Form I has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional theory techniques. Benserazide hydrochloride Form I crystallizes in space group P21/n (#14) with a = 19.22983(15), b = 14.45066(10), c = 4.57982(2) Å, β = 93.6935(3), V = 1270.014(15) Å3, and Z = 4 at 295 K. The crystal structure contains pairs of hydrogen-bonded benserazide cations, which are hydrogen bonded to chloride anions, resulting in chains along the c-axis. In addition, O–H⋯Cl, N–H⋯O, O–H⋯N, and O–H⋯O hydrogen bonds link the cations and anions into a three-dimensional framework. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™ (PDF®).

The crystal structure of decoquinate has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional theory techniques. Decoquinate crystallizes in space group P21/n (#14) with a = 46.8261(5), b = 12.94937(12), c = 7.65745(10) Å, β = 91.972(1), V = 4640.48(7) Å3, and Z = 8 at 295 K. The crystal structure consists of alternating layers of hydrocarbon chains and ring systems along the a-axis. Hydrogen bonds link the ring systems along the b-axis. The rings stack along the c-axis. The two independent decoquinate molecules have very different conformations, one of which is typical and the other has an unusual orientation of the decyl chain with respect to the hydroxyquinoline ring system, facilitating chain packing. The powder pattern has been submitted to the ICDD for inclusion in the Powder Diffraction File™ (PDF®).

Phase characterization with selected area electron diffraction (SAED) represents a significant challenge when the pattern contains a substantial number of diffraction spots arranged in concentric but incomplete rings. This is a common situation when the crystallites are neither large enough to form a single crystal pattern nor sufficiently small and numerous to form continuous Debye-Scherrer rings. In such circumstances, it is often extremely difficult to distinguish between reflections belonging to a specific phase or to identify reflections that originate from secondary phases. To facilitate the process of phase identification for these kinds of multiphase samples, a macro script with the recursive acronym FINDS (FINDS Identifies Non-matrix Diffraction Spots) was developed on the ImageJ/FIJI platform. The program allows the user to mark diffraction spots of known phases by superimposed rings, making it easy to identify and address additional reflections between them. In addition to the full functionality of calculating and plotting the diffraction ring patterns of the known phases in different styles and colors, FINDS also provides tools for locating spot positions and determining the corresponding d-values of the reflections of interest. The effectiveness of this approach and of the developed program in assisting the process of phase identification with SAED patterns of multiphase samples is demonstrated by two representative examples. The macro code of FINDS is published under GNU General Public License v3.0 or later at https://doi.org/10.5281/zenodo.13748483.

The crystal structure of gepirone has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional theory techniques. Gepirone crystallizes in space group P21/a (#14) with a = 16.81794(14), b = 11.71959(5), c = 10.10195(4) Å, β = 95.7012(5)°, V = 1981.239(14) Å3, and Z = 4 at 298 K. The crystal structure consists of discrete gepirone molecules. There are no classical hydrogen bonds in the crystal structure, but several intra- and intermolecular C–H⋯N and C–H⋯O hydrogen bonds contribute to the lattice energy. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™ (PDF®).

X-ray powder diffraction data, unit-cell parameters, and space group for the Lumateperone tosylate, C24H29FN3O⋅C7H7O3S, are reported [a = 15.5848(10) Å, b = 6.0700(4) Å, c = 31.3201(14) Å, β = 96.544(5)°, V = 2943.58 Å3, Z = 4, and space group C2]. In each case, all measured lines were indexed and were consistent with the corresponding space group. The single-crystal data of Lumateperone tosylate is also reported, respectively [a = 15.626(3) Å, b = 6.0806(10) Å, c = 31.415(5) Å, β = 96.609(7)°, V = 2965.1(8) Å3, Z = 4, and space group C2]. The experimental powder diffraction pattern has been well matched with the simulated pattern derived from the single-crystal data with preferred orientation in the [002] direction (orientation coefficient = 0.75).