Syntheses and crystal structures of α methyl alaninium dihydrogen monophosphate and Lβ methyl alaninium dihydrogen monophosphate. An approach for the design and preparation of polar organic-inorganic materials

Abstract

The two following salts have been prepared [(CH 3 ) 2 C(NH 3 )-COOH] + · H 2 P04 (aMADP) and [CH 3 CH 2 CH(NH 3 )COOH] + · H 2 PC>4 (L0MADP). The crystal parameters are: a = 10.060(2), b = 7.634(2), c = 5.852(2) Ä, α = 97.32°(5), β = 107.50°(5), y = 81.16°(5); Z=2; Pi for aMADP and a = 7.164(2), b = 6.533(2), c = 9.458(2) Α; β = 105.48°(7); Ζ = 2; P2i for L/?MADP. Crystal structures were solved by direct methods and refined to a final R value 0.026 with 2889 independent data for aMADP and to R = 0.033 with 2027 reflexions for L/JMADP. Hydrogen atoms located by difference-Fourier syntheses were refined. The layer structure of aMADP and the chain structure of L/?MADP emphasize the importance of H2PO4 polymeric anion and its possible use in the design of polar inorganic materials. The effect of chirality on the anion-aggregation, through the hydrogen bonds, clearly indicated by the L/JMADP structure and some others already described, may be easily transposed to individual, cylic, chain or layer inorganic oxoanions.

Crystallographic, optical and dielectric properties of triclinic α-methyl alaninium dihydrogen monophosphate and α-methyl alaninium dihydrogen monoarsenate

“…Resonance tests on several samples with different orientations showed no piezoelectric effect, so the space group was assumed to be P\. In the case of a-MADP this result is consistent with the data of R. Masse and A. Durif (1990). The unit cell dimensions were refined by least squares methods using the angular data of 36 reflections (for each crystal species) obtained by the Bond-method on a self-built X-ray goniometer.…”

“…Just recently, however, first data (syntheses and crystallographic structures) of one of these compounds were published (Masse and Durif, 1990).…”

“…The unit cell dimensions were refined by least squares methods using the angular data of 36 reflections (for each crystal species) obtained by the Bond-method on a self-built X-ray goniometer. The crystal parameters are summarized in Table 2 together with the published data of a-MADP (Masse and Durif, 1990).…”

“…Metrie data of i-MADP and i-MADA determined by the Bond-method and literature data of i-MADP. ρ χ = 1.834 g/cm 3 ; K=443.8Â 3 ; Z = 2;SG: P\ a Metric data fromMasse and Durif (1990).…”