Abstract
Glycine is a model crystal exhibiting three polymorphic phases and important functional properties such as piezoelectricity and ferroelectricity. We report here in situ observation of the irreversible transformation of the solution-grown glycine crystals from a β phase into a γ phase. The slow transformation process was monitored by piezoresponse force microscopy at room temperature. The process of β to γ conversion was entirely controlled by the variation of relative humidity in the sample chamber. The results show that the rate of phase transformation in glycine is humidity dependent with a threshold of about 25% RH. It is demonstrated that the phase boundary is highly rugged and the transformation front propagates inhomogeneously along the polar axis of the β phase. The mechanism of the phase transformation is discussed.
Original language | English |
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Pages (from-to) | 4138-4142 |
Number of pages | 5 |
Journal | Crystal Growth and Design |
Volume | 14 |
Issue number | 8 |
DOIs | |
Publication status | Published - 6 Aug 2014 |
Externally published | Yes |