The crystal and molecular structure of β-guanidinopropionic acid

Abstract

fl-Guanidinopropionic acid (flGP), C4H9N302, m.p. 215-220°C, is monoclinic, with the following space group and cell dimensions at room temperature: P21/a; a= 11 "818 (4), b= 7-247 (4), c= 7.311 (4)/~, fl= 98.22 (4)°; Z=4, 0ca~c = 1.403, 0 .... = 1"403 g cm -3. Sphenoidal crystals were grown from aqueous solution. Final R=0.061 on 885 observed reflexions. The molecules are folded zwitterions held by hydrogen bonds in planar sheets perpendicular to e. An intramolecular hydrogen bond is found. ExperimentalWeissenberg photographs showed systematic absences for 0k0, k odd and hOl, l odd, uniquely defining the space group as P21/a. A tape-controlled Stoe-Gfittinger diffractometer was used for data collection. Accurate cell dimensions were obtained from a least-squares refinement using the 20 values of 43 reflexions. Intensity data were collected from hnl and hkn layers (n = 0, 1,2,3) up to sin 0/2=0.622 using Ni-filtered Cu Ks radiation (1.5418 A) and a pulse-height analyser. 1131 reflexions were measured of which 106 were systematically extinct, and 85 designated as 'unobselved', i.e. with integrated intensity less than 100 counts above background. The remaining reflexions were regarded as 'observed'.

Structure of guanidinomethylphosphonic acid monohydrate, C2H8N3O3P.H2O

“…ca 2°). The C-N lengths and N--C--N angles are in accord with those in the guanidino moieties of guanidinoacetic acid (Berthou, Laurent & Nakajima, 1976), fl-guanidinopropionic acid (Steward, Warner & Clarke, 1974) and y-guanidinobutyric acid hydrochloride (Maeda, Fujiwara & Tomita, 1972). The guanidino group is nearly planar.…”

A Comprehensive Review on Defects-Induced Voltage Losses and Strategies toward Highly Efficient and Stable Perovskite Solar Cells

“…(Figure 15e,f) This 2D/3D hybrid phase facilitated the passivation of deep-level antisite defects through the dative bond formed between nitrogen atoms and the carbonyl group of β-GUA and the undercoordinated metal cations [273]. Furthermore, strong hydrogen bonding between the β-GUA molecules enhanced device stability by forming a robust organic layer [274]. The extended carrier lifetime from 8.4 µs in the control film to 11.0 µs in 2D/3D heterostructure film and the reduction in defect density N t from 4.57 × 10 16 to 3.69 × 10 16 cm −3 confirmed the passivation effect of a graded junction (see Figure 15g).…”

Structure of agmatine sulphate dihydrate: an extensive amine–sulphate–water hydrogen-bond network

“…1.517 (6) C(7)-N(9) 1.320 ( (Steward, Warner & Clarke, 1974) and yguanidinobutyric acid hydrochloride (Maeda, Fujiwara & Tomita, 1972). The structure exhibits a layerwise packing with the zigzag agmatine chains arranged in planes parallel to ac.…”