15536-15-9Relevant articles and documents
Crystal structure, phase transition and conductivity study of two new organic – inorganic hybrids: [(CH2)7(NH3)2]X2, X?=?Cl/Br
Mostafa, Mohga Farid,El-khiyami, Shimaa Said,Abd-Elal, Seham Kamal
, p. 59 - 73 (2017)
Two hybrids 1,7-heptanediammonium di-halide, [(C7H20N2]X2,X?=?Cl/Br crystallize in monoclinic P21/c, Z?=?4. [(C7H20N2]Cl2: a?=?4.7838 (2)??, b?=?16.9879 (8)??, c?=?13.9476 (8)??, β?=?97.773 (2)°, V?=?1203.58(10)??3, D?=?1.137?g/cm3, λ?=?0.71073??, R?=?0.052 for 1055 reflections with I?>?2σ(I), T?=?298(2)?K. [(C7H20N2]Br2: a?=?4.7952 (10)??, b?=?16.9740 (5)??, c?=?13.9281 (5)??, β?=?97.793 (2)°, V?=?1203.83(6)??3, D?=?1.612?g/cm3, λ?=?0.71073??, R?=?0.03 for 1959 reflections with I?>?2σ(I) T?=?298(2)?K. Asymmetric unit cell of [(C7H20N2]X2,X?=?Cl/Br, each consist of one heptane-1,7-diammonium cation and two halide anions. The organic hydrocarbon layers pack in a stacked herring-bone manner, hydrogen bonded to the halide ions. Lattice potential energy is 1568.59?kJ/mol and 1560.78?kJ/mol, and cation molar volumes are 0.295?nm3 and 0.300?nm3 for chloride and bromide respectively. DTA confirmed chain melting transitions for both hybrids below T?～?340?K. Dielectric and ac conductivity measurements (290??340?K. Cross over from Jonscher's universal dielectric response at low temperatures T??340?K is observed. At high temperatures halide ion hopping in accordance with the jump relaxation model prevails.
Structural characterisation, Hirshfeld surfaces, DSC, periodic DFT modeling, vibrational and optical study of heptylenediammonium pentachlorobismuthate H3N(CH2)7NH3BiCl5
Georgieva, I.,Ouasri, A.,Rhandour, A.,Zahariev, Ts
, (2021/12/20)
A perspective hybrid material, NH3(CH2)7NH3BiCl5, was extensively characterized by structural, DSC, spectroscopic (FT-IR, FT-Raman, and UV-fluorescence) and theoretical (periodic DFT/GGA/PBE) methods. The structural features, noncovalent interactions between molecules in the crystal and electronic structure were examined and discussed in relation to the phase transitions, vibrational characteristics and optical properties. The compound crystallizes at 296 ?K in orthorhombic system (Pbcn space group, Z ?= ?8). The Cl?H/H?Cl intermolecular contacts act as the major contributor (77.2%) in the crystal. The compound was stable from the ambient temperature to 503 ?K, and it underwent one-reversible phase transition of second order type near 498 ?K, at heating. Characteristic bands in FT-IR (400-4000 ?cm-1) and FT-Raman (50-3500 ?cm-1) spectra were interpreted based on factor group analysis and calculated vibrational spectrum. The UV-fluorescence excitation at 396 ?nm and the visible region emission at 483 ?nm, which are of Cl(3p) ? Bi(6p) electron transition character, suggest potential applications as UV-filters and blue photoluminescent emmiters.
Experimental and Computational Models for Side Chain Discrimination in Peptide–Protein Interactions
Lidskog, Anna,Dawaigher, Sami,Solano Arribas, Carlos,Ryberg, Anna,Jensen, Jacob,Bergquist, Karl Erik,Sundin, Anders,Norrby, Per-Ola,W?rnmark, Kenneth
supporting information, p. 10883 - 10897 (2021/07/02)
A bis(18-crown-6) Tr?ger's base receptor and 4-substituted hepta-1,7-diyl bisammonium salt ligands have been used as a model system to study the interactions between non-polar side chains of peptides and an aromatic cavity of a protein. NMR titrations and NOESY/ROESY NMR spectroscopy were used to analyze the discrimination of the ligands by the receptor based on the substituent of the ligand, both quantitatively (free binding energies) and qualitatively (conformations). The analysis showed that an all-anti conformation of the heptane chain was preferred for most of the ligands, both free and when bound to the receptor, and that for all of the receptor-ligand complexes, the substituent was located inside or partly inside of the aromatic cavity of the receptor. We estimated the free binding energy of a methyl- and a phenyl group to an aromatic cavity, via CH-π, and combined aromatic CH-π and π-π interactions to be ?1.7 and ?3.3 kJ mol?1, respectively. The experimental results were used to assess the accuracy of different computational methods, including molecular mechanics (MM) and density functional theory (DFT) methods, showing that MM was superior.
