Selective Growth of a C₇₀ Crystal in a Mixed Solvent System: From Cube to Tube

Abstract

Cube-and tube-shaped C 70 crystals were obtained selectively by reprecipitation using a combination of mesitylene (good solvent) and isopropyl alcohol (poor solvent). Both crystals include mesitylene molecules in their lattices; the ratios of C 70 to mesitylene were 1:2 in C 70 cubes and 1:0.7 in C 70 tubes. The volume ratio of mesitylene to IPA is a key parameter for the selective growth of C 70 cubes and C 70 tubes, rather than the supersaturation ratio, which governs crystal morphology in many other cases. Thus, we propose that the absolute amount of mesitylene near C 70 molecules determines the crystallization pathways for forming the C 70 •2(mesitylene) or C 70 • 0.7(mesitylene) phase, which finally result in C 70 cubes or C 70 tubes, respectively.

Hierarchically Structured Fullerene C70 Cube for Sensing Volatile Aromatic Solvent Vapors

“…The pXRD pattern of HFC ( Figure S23) was indexed as mixed phases of hexagonal (a = 2.527 nm, and c = 1.669 nm) and orthorhombic (a = 2.370 nm, b = 3.228 nm, c = 1.070 nm) structures. [45][46][47] Similar mixed phases have previously been found in porous fullerene C60 crystals. 42,48 The mechanism of structural rearrangement relies initially on the solubility of solvated C70 cube surface in IPA, and solvating mesitylene also plays a key role for this transformation.…”

Unique Crystallization of Fullerenes: Fullerene Flowers

“…Because the sublimation temperatures of both fullerenes are higher than 450 °C, we attributed this loss to mesitylene. That is, mesitylene is the third component of the crystal, as observed in other solvated crystals6716. To assess the ratio of C 60 to C 70 , we used UV-Vis absorption at 335 nm and 383 nm, which is related to the C 60 /[C 60  + C 70 ] ratio (Fig.…”

Diffusion controlling porphyrin assembled structures

“…The rod-like particles are formed at the volume ratio of 95%. Both the strip and rod like particles have a long axis, which is probably caused by the preferential arrangement of molecules by a face to face packing as a result of the p-p stacking [27][28][29]. Although other weak interactions, such as hydrogen bond, van der Waals forces and conjugated interaction, are also present in the selfassembly of porphyrin, the p-p interaction is dominant, especially in the diffusion limitation of molecules [23].…”