Glass-to-cryogenic-liquid transitions in aqueous solutions suggested by crack healing.
Observation of theorized glass-to-liquid transitions between low-density amorphous (LDA) and high-density amorphous (HDA) water states had been stymied by rapid crystallization below the homogeneous water nucleation temperature (∼235 K at 0.1 MPa). We report optical and X-ray observations suggestive of glass-to-liquid transitions in these states. Crack healing, indicative of liquid, occurs when LDA ice transforms to cubic ice at 160 K, and when HDA ice transforms to the LDA state at temperatures as low as 120 K. X-ray diffraction study of the HDA to LDA transition clearly shows the characteristics of a first-order transition. Study of the glass-to-liquid transitions in nanoconfined aqueous solutions shows them to be independent of the solute concentrations, suggesting that they represent an intrinsic property of water. These findings support theories that LDA and HDA ice are thermodynamically distinct and that they are continuously connected to two different liquid states of water.
Cornell High Energy Synchrotron Source (CHESS) and Macromolecular Diffraction Facility at CHESS (MacCHESS), Cornell University, Ithaca, NY 14853; Department of Physics, Ulsan National Institute of Science and Technology, Ulsan 689-798, Republic of Korea; cukim@unist.ac.kr.
Chae Un
CU
Kim
Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853;
Mark W
MW
Tate
Cornell High Energy Synchrotron Source (CHESS) and Macromolecular Diffraction Facility at CHESS (MacCHESS), Cornell University, Ithaca, NY 14853; Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853; Department of Physics, Cornell University, Ithaca, NY 14853; Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY 14853.
Sol M
SM
Gruner
D003460:Crystallization; D005898:Glass; D007053:Ice / Q000032:analysis; D007700:Kinetics; D008962:Models, Theoretical; D055095:Optics and Photonics; D044367:Phase Transition; D011312:Pressure; D012996:Solutions / Q000737:chemistry*; D013696:Temperature; D013816:Thermodynamics; D014867:Water / Q000737:chemistry*; D014961:X-Ray Diffraction
D007053:Ice; D012996:Solutions; D014867:Water
first-order phase transition; glass-to-liquid transition; high-density amorphous ice; low-density amorphous ice; quenched HDA