Supplementary Materialscg400912t_si_001. studied on numerous substrates, in particular anisotropic surfaces seem
Supplementary Materialscg400912t_si_001. studied on numerous substrates, in particular anisotropic surfaces seem FGF2 favorable to conserve the highly anistropic morphology and optical properties, for example, polarized emission or adsorption provided by a parallel molecular orientation obtained by self-assembly.19,20 Consequently, Cu(110),21?23 TiO2(110)24 and muscovite mica(001)4,25?27 are frequently chosen as a proper fundament to study the epitaxial growth of rod-like small molecules. In this paper, the epitaxial growth of 2,2:6,2-ternaphthalene (NNN) on muscovite mica(001) is reported. As indicated in Figure ?Figure1a,1a, the molecule is built from three naphthalene units, which are linked together by NVP-BGJ398 ic50 CCC bonds. Based on morphological and structural analysis, the coexistence of needle-like structures and island-like crystallites is verified. Structural analysis reveals two different crystal orientations. Whereas island-like structures are built up by upright standing molecules orientated with a (001) contact plane relative to the muscovite mica substrate (see Figure ?Figure1b),1b), needles consist of NNN molecules with a (111) lying orientation (see Figure ?Figure1c).1c). Both crystal configurations provide a well-defined azimuthal NVP-BGJ398 ic50 alignment, which is discussed based on force field simulations and a recently reported growth model.26 The azimuthal alignment of island like structures is explained by ledge directed epitaxy at the fiber sidewalls. Open in a separate window Figure 1 (a) The molecular structure of 2,2:6,2-ternaphthalene (NNN). (b) A side view of NNN molecules packed in the observed crystal structure. Each unit cell houses two NNN molecules. Molecules are approximately standing on the S (001) contact plane, which is indicated in blue. (c) A side view along the long molecular axis visualizing the edge-on/flat-on herringbone stacking of NNN. The blue area represents the orientation of the B (111) contact plane where molecules are aligned in almost in lying configuration. Experimental Section Chemical Synthesis of 2,2:6,2-Ternaphthalene (NNN) 2,2:6,2-Ternaphthalene (NNN) was prepared using standard Suzuki cross-coupling procedures.28?30 This all-aromatic compound could be obtained in high yield by coupling 2 equiv of 2-naphthaleneboronic acid (1) with 1 equiv of 2,6-dibromonaphthalene (2), as described in the Supporting Information. The final item, 2,2:6,2-ternaphthalene (NNN), was acquired as a colorless item, which is apparently extremely insoluble in keeping solvents and may only become recrystallized from 1,2,4-trichlorobenzene (colorless platelets). The materials was examined with gas chromatography and mass spectroscopy and discovered to be 99% genuine before thermal sublimation. The yield was 91% after recrystallization from 1,2,4-trichlorobenzene. Sample Planning All samples have already been fabricated on muscovite mica(001) substrates (SPI, Framework Probe, Inc.). Muscovite mica can be a representative of sheet silicate nutrients and a layered framework of light weight aluminum silicate bedding weakly bound by layers of potassium ions. Each coating is seen as a a higher symmetry direction recognized by parallel aligned surface area grooves. Between your individual bedding, the high symmetry path alternates by 120 resulting in a periodic stacking sequence along  direction.25 Soon after cleaving, the mica substrates were used in the hot wall epitaxy (HWE) chamber. The HWE technique was requested the deposition of the organic materials, that allows us to execute the NVP-BGJ398 ic50 growth procedure near thermodynamic equilibrium, and in additional consequence fairly high vapor pressure of the organic deposit in the substrate area may be accomplished. Therefore, certain requirements regarding vacuum circumstances are reduced weighed against, for instance, molecular beam epitaxy.31 The foundation materials NNN was purified twice.