5.2 The Electrodynamics of Confined Water
191
Fig. 5.8 The electric conductivity of water confined in a porous granular medium as a function of
the pore radius r . The inset shows the structure of the sample: bulk water (light blue) coexists with
the interfacial water layer (dark blue) around solid granular particles (gray). Black arrow shows
the trajectory of the proton diffusion. The maximum conductivity value is observed in the pores of
about 2 nm. Adapted with permission from [42]. Copyright 2020 American Chemical Society
Fig. 5.9 I-structures of
a bulk water ( = 80, low
σ dc ), and b interfacial water
( ≈ 2, high σ dc ). Colored
circles are short-lived
spontaneously formed ionic
species of H 3 O + (excess
proton) and OH − (proton
hole). White open circles are
neutral water molecules. The
blue “cloud” is the ionic
atmosphere. F 1 and F 2 are
the driving and restoring
(friction) forces,
respectively. The red arrows
are the effective dipole
moments μ due to relative
displacement of ions
-
-
-
-
+
+
+
+
μ
F 1 =qE
F 2 =kx
F 1 =qE
F 2 ≈0
~1 nm
(b)
(a)
-
-
+
+
+
191
Fig. 5.8 The electric conductivity of water confined in a porous granular medium as a function of
the pore radius r . The inset shows the structure of the sample: bulk water (light blue) coexists with
the interfacial water layer (dark blue) around solid granular particles (gray). Black arrow shows
the trajectory of the proton diffusion. The maximum conductivity value is observed in the pores of
about 2 nm. Adapted with permission from [42]. Copyright 2020 American Chemical Society
Fig. 5.9 I-structures of
a bulk water ( = 80, low
σ dc ), and b interfacial water
( ≈ 2, high σ dc ). Colored
circles are short-lived
spontaneously formed ionic
species of H 3 O + (excess
proton) and OH − (proton
hole). White open circles are
neutral water molecules. The
blue “cloud” is the ionic
atmosphere. F 1 and F 2 are
the driving and restoring
(friction) forces,
respectively. The red arrows
are the effective dipole
moments μ due to relative
displacement of ions
-
-
-
-
+
+
+
+
μ
F 1 =qE
F 2 =kx
F 1 =qE
F 2 ≈0
~1 nm
(b)
(a)
-
-
+
+
+