ISSN:
1573-0689
Keywords:
Alanine and valine enantiomers
;
Chirality
;
Magnetic transition
;
Specific heat anomaly
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Physics
Notes:
Abstract Magnetization of single crystals ofD-,L-alanine andD-valine were measured as a function of temperature using the SQUID magnetometer. An obvious lambda transition at 270 ± 1 K was shown in the specific heat measurement of alanine and valine enantiomers by differential scanning calorimetry (DSC). Magnetic transition temperature seems coincident with that of lambda transition. Temperature dependence of the X-ray powder diffraction forD-valine showed no crystal lattice change under the temperature cooling down from 293 K to 123 K. We propose that the difference of theX ∼T curve between theD-alanine andL-alanine is attributable to the variation of intramolecular geometry of chirality density in the presence of an external magnetic field. The chirality characteristics of alanine and valine enantiomers by the specific heat and susceptibility behaviour are discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00954455
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