I need EBSD patterns from beta-quartz but do not have a heating stage in SEM. Is it possible to get high-quartz prepared and investigated below the transformation temperature because of stabilizing conditions as known for other phases?
Since the quartz inversion is a second order phase transition and therefore depends solely on lattice dynamics (phonons) and not the formation or breakage of bonds, it should not be possible to obtain high quartz at temperatures below the transition temperature, since it cannot be supercooled. This is unfortunate, but cannot be helped. Of course, the transition temperature is affected by pressure, but this will hardly help because Tc increases with pressure (www.minsocam.org/ammin/AM59/AM59_1099.pdf).
Besides, I was wondering what you need these patterns for. In order to get textural information on quartz samples which acquired a texture above Tc you should be able to just do EBSD at ambient temperatures and use the low quartz patterns: the c-axis orientation of the low-quartz will be exactly identical to the original orientation of the c-axis in the high-quartz for each grain (grain boundaries are not affected by the transformation), and unless the sample is strained in some way, there should be equal volume proportions of the two distinct low-quartz orientations resulting from the transformation of every high-quartz crystallite. These two distinct orientational domains are rotated with respect to each other by 60° around the mutual c-axis. Any preferred orientation of the high-quartz should therefore be inherited (subject to the rules stated above) by the low-quartz. No need for fancy experiments unless you are worried about the volume change accompanying the transition, in which case you will have to find a way of measuring at high temperatures.
Beta quartz cannot form or exist at room temperature. Only its pseudomorphic outline can be noticed, if it already existed.
At atmospheric pressure beta quartz cannot be synthesised or studied below 573 deg Celsius.
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