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Small molecular weight organic acids and long carbon chain fatty alcohol composition of a new class of soft X-ray analyzer crystal . Their interplanar spacing with a composed of the ester of the acid with the alcohol carbon chain growth increases. Hydrogen maleate fourteen ester ( THM ) , cetyl hydrogen maleate (HHM ) , 20 hydrogen maleate ester (EHM) belong to this type of organic crystals , wants to be the performance of the soft X-ray spectroscopy crystals. This article with an equimolar ratio of maleic anhydride and the corresponding alcohols synthesis of high purity THM , HHM, the EHM feedstock , THM, HHM, EHM products infrared spectroscopy, the powder diffraction analysis and thermal analysis ; through crystallization experiments Choice the best solvent is benzene, orders crystal growth method for single crystal growing by solution cooling . Growth of the size of 40 × 25 × 2.5mm ~ 3 of THM single crystal and the size of 30 × 25 × 0.5mm3 the EHM monocrystalline . In order to find a suitable solvent cultivate high-quality large single crystals , and theory for the selection of the solvent to provide a basis , and select the appropriate growth temperature range , this paper studies the the EHM supersaturated solution of the nucleation process , and the determination of the induction period , discuss of temperature, supersaturation than the influence on the nucleation rate , calculated by the surface tension of the crystal according to the classical homogeneous nucleation theory , nucleation free and critical nucleation radius. Found that the selection of low crystal growth starting temperature and a smaller control oversaturated than growing conditions conducive to overcome solution spontaneous nucleation tendency . HHM crystal single crystal analysis measured HHM crystals are triclinic , space group P1 | - a = 5.4330 ( 10 ) A | ° , b = 6.8510 ( 7) A | °, c = 29.5650 ( 4 ) A | °, α = 94.8210 (12) °, β = 93.835 (9) °, γ = 103.258 (8) °, Z = 2, V = 1063.1 (2) A | ° 3, crystal molecules through hydrogen bonding form dimers, dimers are arranged in the crystal layer , and thus these layers stacking into a crystalline layer dimer interaction is stronger than the interaction between the layers , the hexadecyl carbon molecule basic atoms coplanar carbon chain into the jagged stretch preliminary interpretation of some phenomenon in the crystal growth process has some properties .
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