Understanding and control of nucleation, growth, habit, dissolution and structure of two- and three-dimensional crystals using `tailor-made' auxiliaries

Abstract

Tailor-made auxiliaries for the control of nucleation and growth of molecular crystals may be classified into two broad categories: inhibitors and promoters. Tailor-made inhibitors of crystal growth can be used for a variety of purposes, which include morphological engineering and etching, reduction of crystal symmetry, assignment of absolute structure of chiral molecules and polar crystals, elucidation of the effect of solvent on crystal growth, and crystallization of a desired polymorph. As for crystal growth promoters, monolayers of amphiphilic molecules on water have been used to induce the growth of a variety of three-dimensional crystals at the monolayer-solution interface by means of structural match, molecular complementarity or electrostatic interaction. A particular focus is made on the induced nucleation of ice by mono- © 1995 International Union of Crystallography Printed in Great Britain -all fights reserved layers of water-insoluble aliphatic alcohols. The twodimensional crystalline structures of such monolayers have been studied by grazing incidence X-ray diffraction. It has become possible to monitor, by this method, the growth, dissolution and structure of self-aggregated crystalline monolayers, and indeed multilayers, affected by the interaction of solvent molecules in the aqueous subphase with the amphiphilic headgroups, and by the use of tailor-made amphiphilic additives.

Mechanism of Calcite Crystal Growth Inhibition by the N-terminal Undecapeptide of Lithostathine

“…This result clearly shows a stronger attachment of pE 1 R 11 to the (11 2 0) face than to the (10 1 4) face. According to theories of crystal growth with additives (35,36), strongly attachment would lead to the appearance of the (11 2 0) face when pE 1 R 11 is present, thus confirming our previous experimental observations (12) . FIG.…”

Etching patterns on the monoclinic and orthorhombic paracetamol

“…This selectivity can be correlated simply with the donor capacity of the etchant molecules (characterized, e.g., by Marcus coefficient 22 ), and this is what was done in our previous work correlating donor numbers of the etching solvents with the anisotropy of the etching pits formed. 2,3,11,12 Alternatively, the interpretation can be based on a more detailed consideration of the possibility of the formation of an intermediate complex between a surface molecule and an etchant molecule ("molecular recognition concept", "key-and-lock" principle).…”

Phase separation of composite materials through simultaneous polymerization and crystallization

“…The results imply that the higher symmetry of the molecular structure provides larger, faceted crystals. 43 Moreover, the substituent on the α position of the carbonyl group inhibits the side reaction leading to the formation of condensed rings. The present phase-separation approach can be applied to inert and miscible combinations of monomers and crystals.…”