Quartz crystals morphology

A variety of surface-sensitive spectroscopic and microscopic methods were critical in the investigation of these systems. In the work by Advincula et al, the composition, thickness, physical and thermal properties, and morphology of the tethered polymer brushes were carefully analyzed [72]. A variety of surface-sensitive techniques such as ellipsometry, contact angle measurements, AFM, quartz crystal microbalance (QCM), FT-IR grazing incidence... 

Figure 4.2. The morphology of quartz crystal predicted by (a) the Bravais empirical law and (b) Donnay-Harker s law.

V. S. Balitsky, H. Iwasaki, and I. Sunagawa, Growth morphologies and their computer simulations in quartz crystals synthesized under various growth conditions, collected abstract of ICCG13/ICVGE 11, 2001, 345... 

We shall start from an analysis of what sort of morphology we should expect for quartz crystals if we entirely neglect the effect of environmental conditions. 

M. Hosaka, T. Miyata, and I. Sunagawa, Growth and morphology of quartz crystals synthesized above the transition temperature,/. Crystal Growth, 152,1995, 300-6... 

H. IwasakiandF. Iwasaki, Morphological variations of quartz crystals as deduced from computer experiments,/. Crystal Growth, 151,1995, 348-58... 

Thickness controllability (Table 9.1, no. 6) and reproducibility in OVPD is achieved by accurate adjustment of the flow of carrier gas by means of mass-flow controllers whereas in VTE quartz crystal monitors are used to control the rate of deposition by adjustment of the evaporation temperature. In VTE small deviations of the evaporation temperature are known to affect the stability of the deposition rate and consequently the layer thickness, which may also affect the roughness and morphology of the VTE-deposited layer. 

Our approach to this problem involves a detailed mechanistic study of model systems, in order to identify the (electro)chemical parameters and the physicochemical processes of importance. This approach takes advantage of one of the major developments in electrochemical science over the last two decades, namely the simultaneous application of /ton-electrochemical techniques to study interfaces maintained under electrochemical control [3-5]. In general terms, spectroscopic methods have provided insight into the detailed structure at a variety of levels, from atomic to morphological, of surface-bound films. Other in situ methods, such as ellipsometry [6], neutron reflectivity [7] and the electrochemical quartz crystal microbalance (EQCM) [8-10], have provided insight into the overall penetration of mobile species (ions, solvent and other small molecules) into polymer films, along with spatial distributions of these mobile species and of the polymer itself. Of these techniques, the one upon which we rely directly here is the EQCM, whose operation and capability we now briefly review. 

Crystal morphologies of (a) left-handed quartz and (b) right-handed quartz. These are readily distinguished by the relative placement of the hemihedial facets. (The figure was adapted from Ref 11.)... 

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