Physical Chemistry Chemical Physics · 2004 · 33 citations · 22 references
Natural SciencesChemistryMaterials ScienceAtmospheric ChemistryInorganic ChemistryPhysical ChemistryHydrate FormationIce ChemistryIce Crystal StructureIce NucleationNucleationAmorphous Ice ChemistryHydrate Formation KineticsNitric Acid FormationPhase Distribution AnalysisStability ConditionsTemperature Effects On Hydrate FormationX-ray Diffraction AnalysisX-ray Diffraction Of Ice
Liquid binary nitric acid/water aerosols (x < 0.25) were shock- frozen (quenched) into X-ray amorphous solids at 35 K. Careful thermal treatment in the temperature interval 35 K < T < 255 K provided the equilibrium phases ice and β-nitric acid trihydrate (β-NAT) as well as the non-equilibrium phases α-NAT, α-nitric acid dihydrate (α-NAD), and nitric acid pentahydrate (NAP, ?). The stability conditions with respect to temperature and composition were determined by X-ray diffraction (XRD) and infrared spectroscopy. In the case of α-NAT they significantly depend on the simultaneous presence of ice such that they overlap with the respective stratospheric conditions.
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