In Situ Observation of the Humidity Controlled Polymorphic Phase Transformation in Glycine Microcrystals

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.

[1]  A. Kholkin,et al.  Growth and Nonlinear Optical Properties of β-Glycine Crystals Grown on Pt Substrates , 2014 .

[2]  S. A. Azhagan,et al.  Structural, mechanical, optical and second harmonic generation (SHG) studies of gamma glycine single crystal , 2013 .

[3]  K. Jensen,et al.  Microfluidic Continuous Seeded Crystallization: Extraction of Growth Kinetics and Impact of Impurity on Morphology , 2012 .

[4]  Sergei V. Kalinin,et al.  Nanoscale Ferroelectricity in Crystalline γ‐Glycine , 2012 .

[5]  M. M. Costa,et al.  Production of Polar β-Glycine Nanofibers with Enhanced Nonlinear Optical and Piezoelectric Properties , 2011 .

[6]  Catherine E. Nicholson,et al.  Leapfrogging Ostwald’s Rule of Stages: Crystallization of Stable γ-Glycine Directly from Microemulsions , 2011 .

[7]  A. Sander,et al.  Crystallization of β‐glycine by spray drying , 2011 .

[8]  N. Surovtsev,et al.  Raman study of low-frequency modes in three glycine polymorphs. , 2011, The Journal of chemical physics.

[9]  A. Kholkin,et al.  Piezoresponse force microscopy studies of the triglycine sulfate-based nanofibers , 2010 .

[10]  E. Salje,et al.  On the dynamics of ferroelastic domain boundaries under thermal and elastic forcing , 2010 .

[11]  Sergei V. Kalinin,et al.  Piezoresponse Force Microscopy: A Window into Electromechanical Behavior at the Nanoscale , 2009 .

[12]  Sergei V. Kalinin,et al.  Electromechanical Imaging and Spectroscopy of Ferroelectric and Piezoelectric Materials: State of the Art and Prospects for the Future , 2009 .

[13]  M. Vijayan,et al.  Head-to-tail sequences and other patterns of peptide aggregation in the solid state , 2009 .

[14]  K. Srinivasan Crystal growth of α and γ glycine polymorphs and their polymorphic phase transformations , 2008 .

[15]  Lian Yu,et al.  Glycine exists mainly as monomers, not dimers, in supersaturated aqueous solutions: implications for understanding its crystallization and polymorphism. , 2008, Journal of the American Chemical Society.

[16]  Benjamin D. Hamilton,et al.  Glycine Polymorphism in Nanoscale Crystallization Chambers , 2008 .

[17]  In Sung Lee,et al.  Concomitant Crystallization of Glycine on Patterned Substrates: The Effect of pH on the Polymorphic Outcome , 2008 .

[18]  Zhimin Liu,et al.  Crystallization of metastable β glycine from gas phase via the sublimation of α or γ form in vacuum , 2008 .

[19]  E. Boldyreva,et al.  Raman observation of a new (ζ) polymorph of glycine , 2006 .

[20]  E. Boldyreva,et al.  Effect of High Pressure on Crystalline Glycine: A New High-Pressure Polymorph , 2004 .

[21]  E. Boldyreva,et al.  Polymorphism of glycine, Part I , 2003 .

[22]  E. Ferrari,et al.  Crystallization in Polymorphic Systems: The Solution-Mediated Transformation of β to α Glycine , 2003 .

[23]  E. Boldyreva,et al.  Synthesis and calorimetric investigation of unstable β-glycine , 2002 .

[24]  A. Bauer-Brandl,et al.  The Polymorphism of Glycine. Thermochemical and structural aspects , 2001 .

[25]  S. Nail,et al.  Characterization of frozen solutions of glycine. , 2001, Journal of pharmaceutical sciences.

[26]  J. Nývlt The Ostwald Rule of Stages , 1995 .

[27]  Takano,et al.  Ansiotropy in friction and molecular stick-slip motion. , 1994, Physical review letters.

[28]  Klaus Christmann,et al.  The interaction of glycine with a platinum (111) surface , 1989 .

[29]  Y. Iitaka Crystal Structure of β-Glycine , 1959, Nature.

[30]  Y. Iitaka The crystal structure of γ‐glycine , 1958 .