Comparative studies of the noncovalent interactions in the single‐crystal packing of pyrene, pyrene‐4,5‐dione, and pyrene‐4,5,9,10‐tetraone

Author(s):  
Monther Zreid ◽  
Zahra A. Tabasi ◽  
Yuming Zhao
Crystals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 390 ◽  
Author(s):  
Jindřich Fanfrlík ◽  
Drahomír Hnyk

Noncovalent interactions in the single crystal of 3,6-Cl2-closo-1,2-P2B10H8 and in the crystal of closo-1,7-P2B10Cl10•toluene were analyzed by means of quantum chemical computations. The crystal packing in the second crystal was dominated by numerous B-Cl···Cl-B dihalogen and strong B-P···π pnictogen bonds, the latter of which were characterized by a small length of 3.08 Å and a large interaction energy value, exceeding −10 kcal mol−1.


Author(s):  
Giulia Novelli ◽  
Charles J. McMonagle ◽  
Florian Kleemiss ◽  
Michael Probert ◽  
Horst Puschmann ◽  
...  

The crystal structure of the monoclinic polymorph of the primary amino acid L-histidine has been determined for the first time by single-crystal neutron diffraction, while that of the orthorhombic polymorph has been reinvestigated with an untwinned crystal, improving the experimental precision and accuracy. For each polymorph, neutron diffraction data were collected at 5, 105 and 295 K. Single-crystal X-ray diffraction experiments were also performed at the same temperatures. The two polymorphs, whose crystal packing is interpreted by intermolecular interaction energies calculated using the Pixel method, show differences in the energy and geometry of the hydrogen bond formed along the c direction. Taking advantage of the X-ray diffraction data collected at 5 K, the precision and accuracy of the new Hirshfeld atom refinement method implemented in NoSpherA2 were probed choosing various settings of the functionals and basis sets, together with the use of explicit clusters of molecules and enhanced rigid-body restraints for H atoms. Equivalent atomic coordinates and anisotropic displacement parameters were compared and found to agree well with those obtained from the corresponding neutron structural models.


2013 ◽  
Vol 834-836 ◽  
pp. 515-518
Author(s):  
Hai Xing Liu ◽  
Qing Liu ◽  
Ting Ting Huang ◽  
Yang Xu ◽  
Lin Tong Wang ◽  
...  

A novel praseodymium complex C5H13O11Pr has been synthesized from hydrothermal reaction and the crystal structure has been determined by means of single-crystal X-ray diffraction. The Pr1 atom is nine coordinated by nine O atoms. The crystal packing is stabilized by O-H...O hydrogen bonding interactions.


Author(s):  
Suresh Suganya ◽  
Kandasamy Saravanan ◽  
Ramakrishnan Jaganathan ◽  
Poomani Kumaradhas

The intermolecular interactions and salt formation of acridine with 4-aminosalicylic acid, 5-chlorosalicylic acid and hippuric acid were investigated. The salts obtained were acridin-1-ium 4-aminosalicylate (4-amino-2-hydroxybenzoate), C13H10N+·C7H6NO3 − (I), acridin-1-ium 5-chlorosalicylate (5-chloro-2-hydroxybenzoate), C13H10N+·C7H4ClO3 − (II), and acridin-1-ium hippurate (2-benzamidoacetate) monohydrate, C13H10N+·C9H8NO3 −·H2O (III). Acridine is involved in strong intermolecular interactions with the hydroxy group of the three acids, enabling it to form supramolecular assemblies. Hirshfeld surfaces, fingerprint plots and enrichment ratios were generated and investigated, and the intermolecular interactions were analyzed, revealing their quantitative contributions in the crystal packing of salts I, II and III. A quantum theory of atoms in molecules (QTAIM) analysis shows the charge–density distribution of the intermolecular interactions. The isosurfaces of the noncovalent interactions were studied, which allows visualization of where the hydrogen-bonding and dispersion interactions contribute within the crystal.


2021 ◽  
Vol 23 (2) ◽  
pp. 68-75
Author(s):  
Altukhov A.A. ◽  

The results of experiments on the study of polarization phenomena and the charge collection efficiency in test structures of diamond ionizing radiation detectors using diamond plates of various types, including single-crystal NRNT-type, single-crystal CVD-type, as well as polycrystalline type, when exposed to alpha-radiation with an energy of 5.5 MeV are presented. Studies have demonstrated the existence of a number of problems with the device quality of diamond plates that affect the performance of spec-trometric-type detectors.


2020 ◽  
Vol 11 (46) ◽  
pp. 12493-12505
Author(s):  
Satoru Inoue ◽  
Toshiki Higashino ◽  
Shunto Arai ◽  
Reiji Kumai ◽  
Hiroyuki Matsui ◽  
...  

An isomorphous bilayer-type layered herringbone crystal packing is reported for a series of four positional isomers of mono-C8-BTNTs, where the single-crystal devices with the isomers exhibit high-performance TFT characteristics.


Author(s):  
M. Rajasekar ◽  
K. Muthu ◽  
A. Aditya Prasad ◽  
R. Agilandeshwari ◽  
SP Meenakshisundaram

Single crystals of molybdenum-incorporated tris(thiourea)zinc(II) sulfate (MoZTS) are grown by the slow evaporation solution growth technique. Crystal composition as determined by single-crystal X-ray diffraction analysis reveals that it belongs to the orthorhombic system with space groupPca21and cell parametersa= 11.153 (2),b= 7.7691 (14),c= 15.408 (3) Å,V= 1335.14 (4) Å3andZ= 4. The surface morphological changes are studied by scanning electron microscopy. The vibrational patterns in FT–IR are used to identify the functional group and TGA/DTA (thermogravimetric analysis/differential thermal analysis) indicates the stability of the material. The structure and the crystallinity of the material were confirmed by powder X-ray diffraction analysis and the simulated X-ray diffraction (XRD) closely matches the experimental one with varied intensity patterns. The band gap energy is estimated using diffuse reflectance data by the application of the Kubelka–Munk algorithm. The relative second harmonic generation (SHG) efficiency measurements reveal that MoZTS has an efficiency comparable to that of tris(thiourea)zinc(II) sulfate (ZTS). Hirshfeld surfaces were derived using single-crystal X-ray diffraction data. Investigation of the intermolecular interactions and crystal packingviaHirshfeld surface analysis reveal that the close contacts are associated with strong interactions. Intermolecular interactions as revealed by the fingerprint plot and close packing could be the possible reasons for facile charge transfer leading to SHG activity.


2014 ◽  
Vol 70 (9) ◽  
pp. 2301-2315 ◽  
Author(s):  
Stephan Gerhard Mauracher ◽  
Christian Molitor ◽  
Rami Al-Oweini ◽  
Ulrich Kortz ◽  
Annette Rompel

Tyrosinases, bifunctional metalloenzymes, catalyze the oxidation of monophenols ando-diphenols too-quinones, the precursor compounds of the brown-coloured pigment melanin. In eukaryotic organisms, tyrosinases are expressed as latent zymogens that have to be proteolytically cleaved in order to form highly active enzymes. This activation mechanism, known as the tyrosinase maturation process, has scientific and industrial significance with respect to biochemical and technical applications of the enzyme. Here, not only the first crystal structure of the mushroom tyrosinaseabPPO4 is presented in its active form (Ser2–Ser383) and in its 21 kDa heavier latent form (Ser2–Thr545), but furthermore the simultaneous presence of both forms within one single-crystal structure is shown. This allows for a simple approach to investigate the transition between these two forms. IsoformabPPO4 was isolated and extensively purified from the natural source (Agaricus bisporus), which contains a total of six polyphenol oxidases (PPOs). The enzyme formed crystals (diffracting to a resolution of 2.76 Å) owing to the employment of the 6-tungstotellurate(VI) salt (Na6[TeW6O24]·22H2O) as a cocrystallization agent. Two of these disc-shaped Anderson-type polyoxoanions [TeW6O24]6−separate two asymmetric units comprising one crystallographic heterodimer ofabPPO4, thus resulting in very interesting crystal packing.


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