Degrees of freedom: Degrees of freedom are ways in which a molecule
or particle can move (e.g., translate, rotate, or vibrate).
Density of states: A function used to represent the number of quantum
mechanical states (filled or unfilled) with particular energies. The
density of states for a molecular system consists of a series of
discrete states, but the density of states of a system with a large
number of electrons (including many nanosystems) exhibits
bands containing many states (see Band Theory).
Desorption: Process of a molecule bound to a surface becoming
detached from that surface and returning to the bulk phase.
Destructive interference: A phenomenon in which light waves combine
to produce a less intense wave or dimmer light area than the
individual waves. This type of interference occurs when the waves
are completely out-of-phase.
Dielectric constant: A dimensionless quantity, also known as the relative
permittivity, that represents the ability of a bulk system to polarize
in response to an electric field.
Dielectric screening: The reduction in strength of electrostatic interactions due to the presence of a dielectric.
Diffusion constant: The constant of proportionality between the flux
(amount of material moving through region) and concentration
gradient in the region.
Diffusion-controlled reaction: A reaction in which the rate-limiting step
is the transport of reactants and products through a system until
they can collide with each other and initiate the remaining steps
of the reaction.
Dimensionality: The number of dimensions in which a system is not
constrained; can apply to translational or rotational degrees of
freedom as well as to the extent of a system/number of dimensions in which the system repeats indefinitely.
Dipole: The simplest multipole, formed by a positive and a negative
charge. The strength of a dipole is called a dipole moment.
Dispersion forces: Force between two instantaneously induced dipoles.
440
Glossary
or particle can move (e.g., translate, rotate, or vibrate).
Density of states: A function used to represent the number of quantum
mechanical states (filled or unfilled) with particular energies. The
density of states for a molecular system consists of a series of
discrete states, but the density of states of a system with a large
number of electrons (including many nanosystems) exhibits
bands containing many states (see Band Theory).
Desorption: Process of a molecule bound to a surface becoming
detached from that surface and returning to the bulk phase.
Destructive interference: A phenomenon in which light waves combine
to produce a less intense wave or dimmer light area than the
individual waves. This type of interference occurs when the waves
are completely out-of-phase.
Dielectric constant: A dimensionless quantity, also known as the relative
permittivity, that represents the ability of a bulk system to polarize
in response to an electric field.
Dielectric screening: The reduction in strength of electrostatic interactions due to the presence of a dielectric.
Diffusion constant: The constant of proportionality between the flux
(amount of material moving through region) and concentration
gradient in the region.
Diffusion-controlled reaction: A reaction in which the rate-limiting step
is the transport of reactants and products through a system until
they can collide with each other and initiate the remaining steps
of the reaction.
Dimensionality: The number of dimensions in which a system is not
constrained; can apply to translational or rotational degrees of
freedom as well as to the extent of a system/number of dimensions in which the system repeats indefinitely.
Dipole: The simplest multipole, formed by a positive and a negative
charge. The strength of a dipole is called a dipole moment.
Dispersion forces: Force between two instantaneously induced dipoles.
440
Glossary