In the title compound, C(48)H(38)N(4)O(8)·C(3)H(6)O(2), the porphyrin mol-ecule is centrosymmetric. The propionic acid solvent mol-ecule is disordered over two sets of sites with equal occupancy factors. The porphyrin central core is almost planar, with an r.m.s. deviation of the fitted atoms of 0.045 Å. The substituent benzene rings make dihedral angles of 70.37 (4) and 66.95 (4)° with respect...

Carboxymethyl cellulose is widely used in many industrial aspects and also in laboratory due to its good biocompatibility. However, special researches on infrared especially aiming at the hydrogen bonds structure of carboxymethyl cellulose were relatively poor. We demonstrate here a full view of infrared spectroscopy in the temperature range of 40–220 C, mainly aiming at the hydrogen bonds in t...

Backbone hydrogen bonds are important for the structure and stability of proteins. However, since conventional site-directed mutagenesis cannot be applied to perturb the backbone, the contribution of these hydrogen bonds in protein folding and stability has been assessed only for a very limited set of small proteins. We have here investigated effects of five amide-to-ester mutations in the back...

In the title melaminium salt, 2,4,6-triamino-1,3,5-triazin-1-ium iodide monohydrate, C(3)H(7)N(6) (+)·I(-)·H(2)O, the components are linked via N-H⋯O, N-H⋯N, O-H⋯I and N-H⋯I hydrogen bonds. All of the H atoms of the melaminium cation are involved in hydrogen bonds. The melaminium cations are inter-connected by four N-H⋯N hydrogen bonds, forming ribbons along [111]. The water mol-ecules connecte...

For further analysis of the effect of nano-doping on the properties of high polymers and research into the mechanism behind modified interfacial hydrogen bonds, a study on the formation probability of nano-SiO2/meta-aramid fibre interfacial hydrogen bonds and the strengthening mechanism behind interfacial hydrogen bonds on the thermal stability of meta-aramid fibres using molecular dynamics is ...

Hydrogen-bonds structure in poly(2-hydroxyethyl methacrylate) (PHEMA) were investigated by means of temperature-dependent infrared (IR) spectroscopy. Spectral variations involved with the OH…OH and C=O…HO types of hydrogen-bonds were found around the glass transition temperature of 80°C. Hydrogen-bonds among the hydroxyl groups gradually dissociate with increasing temperature. In contrast, disc...

An azobenzene bridge was introduced into the lower (or smaller) rim of p-tert-butylcalix[8]arene to form 1,5-singly bridged calix[8]arene derivatives, respectively. Bridged calix[8]arene of conformationally rigid wereisolated. The stability of the two structures of bridged calix[8]arenes have been compared.The study of organicstructure to form nanoporous structures is a well known in chemistry ...

In the structure of the hydrated title salt, (C4H7N2)2[Sn(C2O4)2(OH)2]·H2O, the asymmetric unit comprises one stannate(IV) dianion, two organic cations and one water mol-ecule of crystallization. The [Sn(C2O4)2(OH)2](2-) dianion consists of an Sn(IV) atom chelated by two oxalate anions and coordinated by two OH(-) ligands in a cis octa-hedral arrangement. Neighbouring anions are connected throu...

Structures are reported here for eight further substituted N-aryl-2-chloronicotinamides, 2-ClC(5)H(3)NCONHC(6)H(4)X-4'. When X = H, compound (I) (C(12)H(9)ClN(2)O), the molecules are linked into sheets by N-H...N, C-H...pi(pyridyl) and C-H...pi(arene) hydrogen bonds. For X = CH(3), compound (II) (C(13)H(11)ClN(2)O, triclinic P1 with Z' = 2), the molecules are linked into sheets by N-H...O, C-H....