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Magnetic and Electric Effects on Water
Water, being dipolar, can be partly aligned by an
electric field and this may be easily shown by the movement of
a stream of water by an electrostatic source [163]. Very high field strengths
(5 x 109 V m-1) are required
to reorient water in ice such that freezing is inhibited [251]. Even partial alignment of the water
molecules with the electric field will cause pre-existing
hydrogen bonding to become bent or broken. The balance between
hydrogen bonding and van der Waals attractions is thus biased
towards van der Waals attractions giving rise to less cyclic
hydrogen bonded clustering.
Water is diamagnetic and may be levitated in very high
magnetic fields (10 T, cf. Earth's magnetic field 30
mT) [170]. Lower magnetic fields (0.2 T) have been
shown, in simulations, to increase the number of monomer water
molecules [192] but, rather surprisingly, they increase the
tetrahedrality
at the same time. They may also assist clathrate formation [485]. The increase in refractive index with magnetic
field has been attributed to increased hydrogen bond strength
[647]. These effects are consistent with the magnetic
fields weakening the van der Waals bonding between the water
moleculesa and the water molecules being more tightly
bound, due to the magnetic field reducing the thermal motion
of the inherent charges by generating dampening forces [703]. Due to the fine
balance between the conflicting hydrogen bonding and
non-bonded interactions in water clusters, any such weakening
of the van der Waals attraction leads to a further
strengthening of the hydrogen bonding and greater cyclic
hydrogen bonded clustering. This effect of the magnetic field
on the hydrogen bonding has been further supported by the rise
in the melting point of H2O (5.6 mK at 6 T) and
D2O (21.8 mK at 6 T) [703]
indicating greater ordering (lower entropy) in the liquid
water within a magnetic field. Far greater effects on contact
angle and Raman bands have been shown to occur using strong
magnetic fields (6 T) when the water contains dissolved oxygen
(but not without the oxygen), indicating effects due to
greater clathrate-type water formation [970].
Thus it appears that electric and magnetic fields have
opposite effects on water clustering. Static magnetic effects
have been shown to cause an increase in the ordered structure
of water formed around hydrophobic molecules and colloids [106], as shown by the increase in fluorescence of
dissolved probes [108]. This reinforces the view that it is the
movement through a magnetic field, and it associated
electromagnetic effect, that is important for disrupting the
hydrogen bonding. Such fields can also increase the
evaporation rate of water and the dissolution rate of oxygen
but cannot, despite claims by certain expensive
water preparations, increase the amount of oxygen
dissolved in water above its established, and rather low,
equilibrium concentration [176]. Magnetic fields can also increase proton
spin relaxation [623], which may speed up some reactions dependent on
proton transfer.
Belief in whether or not magnetic or electromagnetic fields
can have any more permanent effect on water, and solutions,
depends on the presence of a working hypothesis for their mode
of action (see also homeopathy).
Such hypotheses are emerging. On a cautionary note however,
many studies either do not treat results with proper
statistical rigor or do not use relevant 'untreated' material
for comparison.
Unstructured water with fewer hydrogen bonds is a more
reactive environment [286], as exemplified by the enhanced reactivity
of supercritical
water.b An open, more hydrogen-bonded network
structure slows reactions due to its increased viscosity,
reduced diffusivities and the less active participation of
water molecules. Any factors that reduce water-water hydrogen
bonding and hydrogen bond strength, such as electric fields,
should encourage reactivity. Water clusters (even with random
arrangements) have equal hydrogen
bonding in all directions. As such, electric or
electromagnetic fields that attempt to reorient the water
molecules should necessitate the breakage of some hydrogen
bonds; e.g. electric fields have been reported to
halve the mean water cluster size as measured by
17O-NMR [111] (see also 'declustered'
water). Electromagnetic radiation (e.g.
microwave) has been shown to exert its effect primarily
through the electrical rather than magnetic effect [455]. The increased hydration ability of water in
electromagnetic fields has been demonstrated by the
dissociation of an enzyme dimer (electric eel
acetylcholinesterase), leading to gel formation, due to the
microwave radiation from a mobile phone [714]. The resultant aqueous restructuring caused by
such processes may be kinetically stable.
Pure water is a poor
conductor of electricity but is not a perfect
insulator as it always contains ions due to self-ionization.
Passage of an electric current causes electrolysis,
producing O2 at the anode and H2 at the
cathode. At metallic electrodes, even quite low voltages can
have impressive effects on the orientation of the water
molecules and the positioning of ions [375].c A negative potential of -0.23 V orients
water hydrogen atoms towards the electrode whereas +0.52 V
reverses this; both causing some hydrogen bond breakage and
localized density increase.d Ions are attracted or repelled dependent on
their charge. Similar orientations may take place at the
surface of minerals containing alternating positive and
negative charges such that a solid (static and
non-exchangeable) water layer has been reported at the surface
of highly polar metal oxides, (e.g. TiO2)
and an ambient temperature single layer ice (with all the
donor hydrogen bonds oriented towards each other or the silica
surface oxygen atoms) is found, using modeling, on the surface
of hydrophilic fully hydroxylated silica ([701], called ice tesselation), which may explain the
many layers of structured water found at the surfaces of
complex silicates. Thus, a high-voltage electric field (333 kV
m-1) has been shown to raise the water
activity in bread dough, so ensuring a more efficient
hydration of the gluten [331] and treatment of water with magnetic fields
of about one Tesla increases the strength of mortar due to its
greater hydration [426]. Rather unexpectedly, such electric fields (~1
MV m-1) apparently increase water's surface tension
by about 2% [680].e
High interfacial fields (E > 109 V
m-1) at electrode (or charged) surfaces can cause a
phase transition with an ordered layering of water at high
densities similar to ice
X [420], whereas lower fields (E =106 V
m-1) may cause lower density freezing transitions
at room temperature [873]. High fields (E ~109 V
m-1) might also be found (perhaps surprisingly) at
the surface of hydrophilic molecules where caused by the
partial charges on the atoms and the small distances between
the surface and first hydration layer. High fields affect hydrogen
bonding in an anisotropic manner, hydrogen bonds being
strengthened along the field but weakened orthogonal to the
field [582]. At low fields, however, both translational and
rotational motions may be reduced. Electric fields also lower
the dielectric constant of the water [616], due
to the resultant partial or complete destruction of the
hydrogen-bonded network. Consequentially, the solubility
properties of the water will change in the presence of such
fields and may result in the concentration of dissolved gasses
and hydrophobic molecules at surfaces followed by reaction
(e.g. due to reactive singlet oxygen
(1O2) or free radical formation such as
OH•) or phase changes (e.g. formation of flattish
surface nanobubbles [506]). Such changes can clearly result in effects
lasting for a considerable time, giving rise to claims for
'memory' effects. One of the curious facts, concerning reports
of the effects of magnets and electromagnetic radiation on the
properties of water, is the long lifetime these effects seem
to have (e.g. [757]). This should not be so surprising, however, as
it can take several days for the effects, of the addition of
salts to water, to finally stop oscillating [4].
Also, there is evidence that water structuring in still
deaerated pure water increases over a period of a day or two
[509], clathrates may persist metastably in water [485],
water restructuring after infrared radiation persists for more
than a day [730], and water photoluminescence (possibly due to
impurities at gas/liquid interfaces [800b]) changes over a period of days [801]. Permanent changes to the structure of water
are reported following exposure to resonant RLC (resistance
inductance capacitance) circuits [927]. The effects, however, are small and poorly
reproducible and, as with some of the other studies mentioned
here, should be viewed with the possibility that pathological science is at work.
In addition to the breakage of hydrogen bonds
electromagnetic fields may perturb in the gas/liquid interface
and produce reactive oxygen species [110].
Changes in hydrogen bonding may effect carbon dioxide
hydration resulting in pH changes. Thus the role of dissolved
gas in water chemistry is likely to be more important than
commonly realized [459]; particularly as the formation of nanobubbles
[506]
containing just a few hundred or less molecules of gas, the
stability of larger bubbles (~300 nm diameter) detected by
light scattering [800a] and
nanobubble coating of hydrophobic surfaces [803] have all been recently described. Reinforcement
of this view comes from the effect of magnetized water on
ceramic manufacture [601] and out-gassing experiments that apparently
result in the loss of magnetic and electromagnetic effects [110, 800a] or
photoluminescent effects [800b]. Gas
accumulating at hydrophobic surfaces [459b]
promotes the hydrophobic
effect and low-density water formation. The accumulated
gas molecules at such hydrophobic surfaces becomes
supersaturating when electromagnetic effects disrupt this
surface low-density water. An interesting (and possibly
related) 'memory of water' phenomena is the effect of water,
previously exposed to weak electromagnetic signals, on the
distinctive patterns and handedness of colonies of certain
bacteria [971]. Here, the water retains the effect for at
least 20 minutes after exposure to the field.
Recently, there has been some debate over
'digital
biology'; a proposal from Jacques Benveniste (leader of
the team that produced the controversial
homeopathy paper) that 'specific molecular signals in the
audio range' (hypothetically the 'beat' frequencies of water's
infrared vibrations) may be heard, collected, transmitted
(e.g. by phone) and amplified to similarly affect
other water molecules at a receiver [134]. This unlikely idea is generally thought
highly implausible. The data has, however, reportedly been
independently confirmed but this has not yet been published
(which may be rather problematic in the present skeptical
climate). Note that experimental confirmation of the
phenomenon may not necessarily confirm the proposed mechanism.
Rather interestingly, however, electromagnetic emission has
been detected during the freezing of supercooled water [297] due to negative charging of the solid
surface at the interface caused by surface ionization of water
molecules followed by preferential loss of hydrogen ions [462]; a consequence, perhaps, of the Costa Ribeiro
effect [551]. It is not unreasonable, therefore, that
similar effects may occur during changes in the structuring of
liquid water. Also, it has been reported that microwave
frequencies can also give rise to signals audible to radar
operators [356].
If electromagnetic effects do indeed
influence the degree of structuring in water, then it is clear
that they may have an effect on health. The biological effects
of microwaves, for example, have generally been analyzed in
terms of their very small heating effects. However, it should
be recognized that there might be significant non-thermal
effects (e.g. [714]) due
to the imposed re-orientation of water at the surfaces of
biomolecular structures such as membranes [356].
Similar effects on membranes have been proposed to occur due
to magnetic fields [657]. Additionally as low-frequency, low level
alternating electric fields have been found to affect the
electrical conductivity of pure water [358], the effects of living near power cables and
microwave towers should, perhaps, not be thought harmless just
because no theory for harm has been formally recognized. Even
variations in the geomagnetic field may have some long-term
exposure effects.
a This effect has been
demonstrated in weakly bound van der Waals complexes as due to
the coupling between magnetic-field induced energy levels
(Zeeman levels) of the molecular orbitals [659]. [Back]
b Note that this may not extend to
conditions of much-reduced hydrogen bonding. At close to
critical and supercritical conditions, water molecules may
become less reactive than expected with temperature increase
due to the loss of hydrogen bonding causing consequential loss
of the 'cage' effect, which encourages reactions within the
'cage', and reduced polarization activation. [Back]
c Note that the electric field
strength across the surface monolayer of water molecules may
be of the order of 1010 V m-1 for just a
few volts applied potential. [Back]
d The binding of water molecules
to uncharged metal surfaces depends on the nature of the
metal. On a platinum Pt(111) surface, half the water molecules
form Pt····OH2 links with the other half forming
Pt····H-OH bonds due to the balance between Pt····H hydrogen
bond formation and H-O bond weakening. Other metal surfaces
may prefer one or the other water orientation or cause partial
dissociation of the protons dependent on their proton affinity
[523]. [Back]
e Electric and magnetic fields
lower the surface tensions of natural
water by up to 8% [735]. However, it has been noted elewhere that
surface tension measurements are too sensitive to impurities
to provide reliable data [979]. [Back]
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