Quantum states with more energy than the lowest possible amount
After absorbing energy, an electron may jump from the ground state to a higher energy excited state.Excitations of copper 3d orbitals on the CuO2 plane of a high-Tc superconductor. The ground state (blue) is x2–y2 orbitals; the excited orbitals are in green; the arrows illustrate inelastic x-ray spectroscopy.
In quantum mechanics, an excited state of a system (such as an atom, molecule or nucleus) is any quantum state of the system that has a higher energy than the ground state (that is, more energy than the absolute minimum). Excitation refers to an increase in energy level above a chosen starting point, usually the ground state, but sometimes an already excited state. The temperature of a group of particles is indicative of the level of excitation (with the notable exception of systems that exhibit negative temperature).
The lifetime of a system in an excited state is usually short: spontaneous or induced emission of a quantum of energy (such as a photon or a phonon) usually occurs shortly after the system is promoted to the excited state, returning the system to a state with lower energy (a less excited state or the ground state). This return to a lower energy level is often loosely described as decay and is the inverse of excitation.
Long-lived excited states are often called metastable. Long-lived nuclear isomers and singlet oxygen are two examples of this.
an excitedstate of a system (such as an atom, molecule or nucleus) is any quantum state of the system that has a higher energy than the ground state (that...
(2005) "Excited" (M People song) (1992) Excitation (disambiguation) Excitedstate, an elevation in energy level above an arbitrary baseline energy state Exciter...
singlet ground state is excited (via absorption of radiation) to a higher energy level, either an excited singlet state or an excited triplet state will form...
Excitedstate intramolecular proton transfer (ESIPT) is a process in which photoexcited molecules relax their energy through tautomerization by transfer...
An excitedstate is any state with energy greater than the ground state. In quantum field theory, the ground state is usually called the vacuum state or...
short for excited dimer) is a short-lived polyatomic molecule formed from two species that do not form a stable molecule in the ground state. In this case...
a group of atoms or molecules) exists in a state in which more members of the system are in higher, excited states than in lower, unexcited energy states...
nuclide. Except for gamma decay or internal conversion from a nuclear excitedstate, the decay is a nuclear transmutation resulting in a daughter containing...
nuclear isomer is a metastable state of an atomic nucleus, in which one or more nucleons (protons or neutrons) occupy excitedstate (higher energy) levels. "Metastable"...
Fluorescence occurs when an excited molecule, atom, or nanostructure, relaxes to a lower energy state (usually the ground state) through emission of a photon...
Photoinduced electron transfer (PET) is an excitedstate electron transfer process by which an excited electron is transferred from donor to acceptor...
the vibrationally excitedstate of the electronic excitedstate. The process of the energy relaxation from these vibrationally excited states can be observed...
a molecule or atom) absorbs a photon, it gains energy and enters an excitedstate. The system can relax by emitting a photon. The Stokes shift occurs...
Consider, for example, an atom with ground state angular momentum J = 1 2 {\textstyle J={\frac {1}{2}}} and excitedstate angular momentum J ′ = 3 2 {\textstyle...
must be in the proper excitedstate so that the photons can trigger them. In most materials, atoms or molecules drop out of excited states fairly rapidly...
the form of light). Sometimes, the excitedstate is metastable, so the relaxation back down from the excitedstate to lower states is delayed (necessitating...
ground state. If it is at a higher energy level, it is said to be excited, or any electrons that have higher energy than the ground state are excited. An...
of a specific frequency can interact with an excited atomic electron (or other excited molecular state), causing it to drop to a lower energy level....
states (0 is the ground state, and 1 the excitedstate). Transitions can also occur to higher energy levels, but the first excitedstate is denoted for simplicity...
approximations, such as the Hartree–Fock method, can be used to estimate the ground state energy and wavefunction of the atom. Historically, the first such helium...
state where all electrons are spin paired. It is kinetically unstable at ambient temperature, but the rate of decay is slow. The lowest excitedstate...
in the medium, producing excited states in its atoms. When for a period of time the number of particles in one excitedstate exceeds the number of particles...
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