Potential energy (V): Energy stored within a system due to its position in
a force field.
Profilometry: A mechanical method for measuring the thickness of a
film by measuring motion of a very sharp stylus across a substrate.
Pseudo-first-order approximation: An approximation that assumes
that the concentrations of all but one reacting species in a reaction
are nearly constant such that the rate law can be written as a
function of only one species.
Pyroelectric effect: An effect found in certain materials where heating
the material induces an electric field in the material.
Rate of reaction: The change in the concentration of a reacting species
as a function of time during a reaction (e.g., the first derivative of
the concentration of a reactant or product with respect to time).
Rate-limiting (determining) step: The slowest elementary step in a
reaction, which determines the rate of the entire reaction.
Reaction mechanism: The series of elementary steps that leads from
reactants to products for a specific reaction. The sum of the elementary steps yields the stoichiometric equation.
QCM: Quartz crystal microbalance.
Quantization of energy: The quantum mechanical principal that within
a confined system, only certain values of energy are allowed for
the system.
Quantum confinement: The change in the properties of a system due to
the electrons in a system being trapped in a nanoscale region. The
dimensionality of quantum confinement is defined by the
number of directions in which the movement of electrons is not
confined.
Quantum dots: Quantum dots are inorganic semiconductor nanoparticles, typically 2−10 nm in size. The excitons (electron-hole
pairs) of quantum dots are confined to three dimensions.
Quantum dots typically consist of a core, shell, and final coat, as
shown in Figure 5.10. They are characterized by the nature of each
of these layers, their size and aspect ratio, their quantum efficiency in optical materials, and their coercivity in magnetic
materials. Properties of an ensemble of quantum dots are
452
Glossary
a force field.
Profilometry: A mechanical method for measuring the thickness of a
film by measuring motion of a very sharp stylus across a substrate.
Pseudo-first-order approximation: An approximation that assumes
that the concentrations of all but one reacting species in a reaction
are nearly constant such that the rate law can be written as a
function of only one species.
Pyroelectric effect: An effect found in certain materials where heating
the material induces an electric field in the material.
Rate of reaction: The change in the concentration of a reacting species
as a function of time during a reaction (e.g., the first derivative of
the concentration of a reactant or product with respect to time).
Rate-limiting (determining) step: The slowest elementary step in a
reaction, which determines the rate of the entire reaction.
Reaction mechanism: The series of elementary steps that leads from
reactants to products for a specific reaction. The sum of the elementary steps yields the stoichiometric equation.
QCM: Quartz crystal microbalance.
Quantization of energy: The quantum mechanical principal that within
a confined system, only certain values of energy are allowed for
the system.
Quantum confinement: The change in the properties of a system due to
the electrons in a system being trapped in a nanoscale region. The
dimensionality of quantum confinement is defined by the
number of directions in which the movement of electrons is not
confined.
Quantum dots: Quantum dots are inorganic semiconductor nanoparticles, typically 2−10 nm in size. The excitons (electron-hole
pairs) of quantum dots are confined to three dimensions.
Quantum dots typically consist of a core, shell, and final coat, as
shown in Figure 5.10. They are characterized by the nature of each
of these layers, their size and aspect ratio, their quantum efficiency in optical materials, and their coercivity in magnetic
materials. Properties of an ensemble of quantum dots are
452
Glossary