Thomas Loerting

Nicolas Giovambattista2
Mario J. Molina2
Katrin Amann-Winkel2
2Nicolas Giovambattista
2Mario J. Molina
2Katrin Amann-Winkel
Learn More
  • Hartawan Laksmono, Trevor A. McQueen, Jonas A. Sellberg, N. Duane Loh, Congcong Huang, Daniel Schlesinger +15 others
  • 2015
Classical nucleation theory (CNT). According to CNT, 1–4 the homogeneous ice nucleation rate at which critical nuclei appear within a supercooled liquid can be expressed by 1–7 í µí°½ = í µí°½ 0 exp (− ∆í µí°¹ * í µí±˜í µí±‡), where J0 is the temperature-dependent pre-exponential factor, and ∆í µí°¹ * is the Gibbs free energy barrier to form a critical(More)
The freezing of aqueous solutions and reciprocal distribution of ice and a freeze-concentrated solution (FCS) are poorly understood in spite of their importance in fields ranging from biotechnology and life sciences to geophysics and climate change. Using an optical cryo-microscope and differential scanning calorimetry, we demonstrate that upon cooling of(More)
Water has multiple glassy states, often called amorphous ices. Low-density (LDA) and high-density (HDA) amorphous ice are separated by a dramatic, first-order like phase transition. It has been argued that the LDA-HDA transformation connects to a first-order liquid-liquid phase transition (LLPT) above the glass transition temperature T(g). Direct(More)
We perform out-of-equilibrium molecular dynamics (MD) simulations of water-glycerol mixtures in the glass state. Specifically, we study the transformations between low-density (LDA) and high-density amorphous (HDA) forms of these mixtures induced by compression/decompression at constant temperature. Our MD simulations reproduce qualitatively the density(More)
Calorimetric and optical cryo-microscope measurements of 10-64 wt % citric acid (CA) solutions subjected to moderate (3 K/min) and slow (0.5 and 0.1 K/min) cooling/warming rates and also to quenching/moderate warming between 320 and 133 K are presented. Depending on solution concentration and cooling rate, the obtained thermograms show one freezing event(More)
Several proton-disordered crystalline ice structures are known to proton order at sufficiently low temperatures, provided that the right preparation procedure is used. For cubic ice, ice Ic, however, no proton ordering has been observed so far. Here, we subject ice Ic to an experimental protocol similar to that used to proton order hexagonal ice. In situ(More)
Twenty years ago two different polymorphs of carbonic acid, α- and β-H2CO3, were isolated as thin, crystalline films. They were characterized by infrared and, of late, by Raman spectroscopy. Determination of the crystal structure of these two polymorphs, using cryopowder and thin film X-ray diffraction techniques, has failed so far. Recently, we succeeded(More)
Organic acids play an important role in the acidification of our atmosphere. These weak acids can contribute up to 60 % of the free airborne acidity. By far the most abundant organic acids are the C1 and C2 monocarboxylic acids, formic acid (HCOOH) and acetic acid (CH 3 COOH), which show mixing ratios in the gas phase ranging up to 20 ppb over land [1, 2](More)
We report in situ density values of amorphous ice obtained between 0.3 and 1.9 GPa and 144 to 183 K. Starting from high-density amorphous ice made by pressure-amorphizing hexagonal ice at 77 K, samples were heated at a constant pressure until crystallization to high-pressure ices occurred. Densities of amorphous ice were calculated from those of(More)