Waterdefekte

Waterdefekte are structural irregularities involving water molecules or water-containing species within a material. The term encompasses deviations from an ideal, uniform arrangement of water in ice, hydrates, clays, polymers, cementitious materials and other porous or hydrated systems. Defects can involve the hydrogen-bond network, the presence of water-derived ions, or misplaced water molecules, and they generally affect transport, mechanical properties and phase behavior.

In crystalline ice, waterdefekte arise when the local hydrogen-bond network deviates from the ice rules. Common categories include Bjerrum defects (D- and L-defects) describing violations of proton placement, and ionic defects such as hydronium (H3O+) and hydroxide (OH−) created by proton transfer. These defects influence proton conductivity, dielectric response and diffusion within ice.

In water-containing materials, defects may be vacancies, intercalated water, hydroxyl groups, or proton-disordered regions within hydrates, clays, zeolites, polymers and cement. They can form during hydration, dehydration, irradiation, or mechanical stress and can modify transport properties, swelling, and structural stability.

Detection and characterization rely on techniques such as infrared and Raman spectroscopy, nuclear magnetic resonance, neutron scattering and impedance measurements to assess defect concentrations and dynamics.

Significance: understanding waterdefekte is important for geophysical processes (water transport in ice and minerals), cryobiology and cryomaterials, as well as for technologies relying on hydrated systems and porous materials, including fuel cells, cement chemistry, and polymer electrolytes. See also hydrogen-bond network, proton conduction, and defect chemistry.