Gibbs energy: A state function representing the energy of a system at
constant pressure. Systems at constant pressure are at equilibrium when ΔG = 0 and processes at constant pressure are spontaneous when ΔG < 0.
Graphene: Atomically thin layers of graphite, consisting of sheets of sp
2
carbon atoms arranged in hexagonal rings.
Gravimetry: Measurement techniques that characterize a material’s
response to gravity (weight), which in turn allows determination
of their mass.
H-type aggregate: One-dimensional molecular assembly in which the
dipole moments are aligned parallel to each other but perpendicular to the line joining their centers. This is sometimes referred
to as the “face-to-face arrangement.”
Half-life: The time taken for the concentration of a reactant to reach half
of its initial value during a reaction, equal to ln(2)/k, where k is the
rate constant for the reaction.
Hamiltionian: An operator that describes the kinetic and potential
energy of a system in terms of coordinates in space.
Hard sphere model: A way to determine atomic radius by assuming
atoms in a solid are hard spheres and pack closely together.
Harmonic oscillator: A model quantum mechanical system in which
particles are confined to a region defined by a quadratic function.
Typically used to represent molecular vibrations.
Heisenberg uncertainty principle: A key principle in quantum mechanics
stating that for certain pairs of variables, such as position and
momentum or time and energy, it is impossible to determine the
values of both values to infinite precision. Beyond a certain limit, an
increase in the precision in which one variable is known decreases
the precision to which the other variable may be measured.
Hill equation: An equation that relates the equilibrium constant of a
reaction involving many small molecules (ligands) binding to a
large molecule (macromolecule) with many potential binding
sites to the concentration of the ligand and the concentration of
binding sites, under the assumption that all of the binding sites
are identical but that binding at one site may affect binding at
others (cooperative binding).
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Glossary
constant pressure. Systems at constant pressure are at equilibrium when ΔG = 0 and processes at constant pressure are spontaneous when ΔG < 0.
Graphene: Atomically thin layers of graphite, consisting of sheets of sp
2
carbon atoms arranged in hexagonal rings.
Gravimetry: Measurement techniques that characterize a material’s
response to gravity (weight), which in turn allows determination
of their mass.
H-type aggregate: One-dimensional molecular assembly in which the
dipole moments are aligned parallel to each other but perpendicular to the line joining their centers. This is sometimes referred
to as the “face-to-face arrangement.”
Half-life: The time taken for the concentration of a reactant to reach half
of its initial value during a reaction, equal to ln(2)/k, where k is the
rate constant for the reaction.
Hamiltionian: An operator that describes the kinetic and potential
energy of a system in terms of coordinates in space.
Hard sphere model: A way to determine atomic radius by assuming
atoms in a solid are hard spheres and pack closely together.
Harmonic oscillator: A model quantum mechanical system in which
particles are confined to a region defined by a quadratic function.
Typically used to represent molecular vibrations.
Heisenberg uncertainty principle: A key principle in quantum mechanics
stating that for certain pairs of variables, such as position and
momentum or time and energy, it is impossible to determine the
values of both values to infinite precision. Beyond a certain limit, an
increase in the precision in which one variable is known decreases
the precision to which the other variable may be measured.
Hill equation: An equation that relates the equilibrium constant of a
reaction involving many small molecules (ligands) binding to a
large molecule (macromolecule) with many potential binding
sites to the concentration of the ligand and the concentration of
binding sites, under the assumption that all of the binding sites
are identical but that binding at one site may affect binding at
others (cooperative binding).
444
Glossary