Morphology and Crystal Structure

The lattice constant along the c-axis is reported very close to 7.8 A and related to that for the polythiophene (without substituents), implying again the stretched 

In relation to the specific effects described above, electrochemically synthesized polythiophenes also exhibit interesting morphologies [17, 30, 31, 33]. The STM images again indicate that the (super)helical structures are involved. The cooperation between the host polymers and dopant ions seems responsible for those structures as well. In this context, Hotta [37] pointed out that rapid deposition of the polymer chains that follows umnediately after the electrochemical generation of those polymers may well lead to rather unusual crystal structures. 

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Selected area diffraction (SAD) combined with microscopy is an important supplementary tool to X-ray diffraction in crystal structure analysis. SAD has the additional advantage of giving the correlation between morphology and crystal structure whenever single crystals are too small for single-crystal X-ray analysis. 

CdSe thin films and CdSe nanocrystal layers were electrodeposited on Ti or ITO substrates in solutions containing CdS04 and H2Se03 at pH 2.5 [188, 189]. The influence of different deposition potentials on the surface morphology and crystal structure of CdSe Aims was studied. 

Yuan B-L, Rybnikar F, Saha P, Geil PH (1999) Phase I and II crystals of poly(p-oxybenzoate). II. Effects of solution polymerization conditions on morphology and crystal structure. J Polym Sci Polym Phys Ed 37 3532... 

To study the impact of the initial solution pH on particle morphology and crystal structure in the ACS process, BT gels were formed at pH 12, 14, and 14.2 for BTl, BT2, and BT3, respectively. The room temperature XRD patterns in Figure 7.1 indicate that the pH needs to be greater than 12 for BT powders to be crystalline. At pH 14.0 and 14.2, the powders were crystallized into cubic phase BT. It can be concluded that alkalinity plays an important role in the crystallization of BT in the ACS process. According to the thermodynamic model for the hydrothermal process, phase-pure BT can only be obtained at a pH higher than 13.5. 

Judging from the morphology and crystal structure, tliat is, rounded slrapc and single crystal, it seems reasonable to assume that tlie carbyne without vacancy sublattice obtained in the present work was formed from vapor rather than that it was formed by the solid-solid sequence of pliase transformations in the turbostratic graphite. 

The effect of ultrasonic irradiation on the mechanical property, morphology, and crystal structure of PP/EPDM blends were examined by Chen and Li (16). Appropriate ultrasonic intensity can increase the toughness of PP/EPDM blends noticeably. SEM showed that with ultrasonic irradiation, the morphology of a well-dispersed EPDM phase is formed in the PP/EPDM blend. Ultrasonic irradiation interestingly... 

Chen J, Chen J, Zhu S, Cao Y, Li H (2011) Mechanical properties, morphology, and crystal structure of polypropylene/chemically modified attapulgite nanocomposites. J Appl Polym Sci 121 899-908... 

Needle-like HAp nanocrystals having a similar morphology and crystal structure to natural apatite (average size of 50 x 25 nm and thickness of 2-3 nm) have been synthesized by hydrothermal methods [54]. 

Ever since three-dimensional crystal structures have been known, researchers have been searching for a relationship between morphology and crystal structure. From a purely thermodynamic perspective, this relationship can be elucidated by measuring or calculating the surface energy of the individual crystal faces. The thermodynamically most stable crystal polyhedron is the one possessing the lowest overall surface energy. 

Yang J, Sidoti G, Liu J, Geil P, Li C, Cheng S. Morphology and crystal structure of CTFMP and bulk polymerized poly (trimethylene terephthalate). Polymer 2001 42 7181-7195. 

Earl, W.L., and Vanderhart, D.L., 1981, Observation by high-resolution carbon-13 NMR of cellulose I related to morphology and crystal structure, Macromol., 14 570. 

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