“energy level”的概念、定义、翻译、参考文献-科学参考

energy level

Physics

A definite fixed energy that a system described by quantum mechanics, such as a molecule, atom, electron, or nucleus, can have. In an atom, for example, the atom has a fixed energy corresponding to the orbitals in which its electrons move around the nucleus. The atom can accept a quantum of energy to become an excited atom (see excitation) if that extra energy will raise an electron to a permitted orbital. Between the ground state, which is the lowest possible energy level for a particular system, and the first excited state there are no permissible energy levels. According to the quantum theory, only certain energy levels are possible. An atom passes from one energy level to the next without passing through fractions of that energy transition. These levels are usually described by the energies associated with the individual electrons in the atoms, which are always lower than an arbitrary level for a free electron. The energy levels of molecules also involve quantized vibrational and rotational motion.

Astronomy

The discrete energy state of an electron in an atom or molecule. Electrons can occupy only specific energy levels and jump from one energy level to another. The lowest energy level is called the ground state of the atom or molecule. Within an atom, energy levels correspond to the distance from the nucleus. The electron requires energy to jump from a state of lower energy (an energy level close to the nucleus) to a higher energy level (further from the nucleus); the atom is then said to be excited. Energy levels are defined by a quantum number, symbol n. For the ground state, n = 1. Higher energy levels are numbered 2, 3, etc., outwards from the nucleus. When an electron jumps from a higher energy level to a lower energy level it emits a photon, the energy of which is equal to the difference between the two energy levels.

Chemistry

A definite fixed energy that a molecule, atom, electron, or nucleus can have. In an atom, for example, the atom has a fixed energy corresponding to the orbitals in which its electrons move around the nucleus. The atom can accept a quantum of energy to become an excited atom (see excitation) if that extra energy will raise an electron to a permitted orbital. Between the ground state, which is the lowest possible energy level for a particular system, and the first excited state there are no permissible energy levels. According to the quantum theory, only certain energy levels are possible. An atom passes from one energy level to the next without passing through fractions of that energy transition. These levels are usually described by the energies associated with the individual electrons in the atoms, which are always lower than an arbitrary level for a free electron. The energy levels of molecules also involve quantized vibrational and rotational motion.

单词	energy level
释义	energy level Physics A definite fixed energy that a system described by quantum mechanics, such as a molecule, atom, electron, or nucleus, can have. In an atom, for example, the atom has a fixed energy corresponding to the orbitals in which its electrons move around the nucleus. The atom can accept a quantum of energy to become an excited atom (see excitation) if that extra energy will raise an electron to a permitted orbital. Between the ground state, which is the lowest possible energy level for a particular system, and the first excited state there are no permissible energy levels. According to the quantum theory, only certain energy levels are possible. An atom passes from one energy level to the next without passing through fractions of that energy transition. These levels are usually described by the energies associated with the individual electrons in the atoms, which are always lower than an arbitrary level for a free electron. The energy levels of molecules also involve quantized vibrational and rotational motion. Astronomy The discrete energy state of an electron in an atom or molecule. Electrons can occupy only specific energy levels and jump from one energy level to another. The lowest energy level is called the ground state of the atom or molecule. Within an atom, energy levels correspond to the distance from the nucleus. The electron requires energy to jump from a state of lower energy (an energy level close to the nucleus) to a higher energy level (further from the nucleus); the atom is then said to be excited. Energy levels are defined by a quantum number, symbol n. For the ground state, n = 1. Higher energy levels are numbered 2, 3, etc., outwards from the nucleus. When an electron jumps from a higher energy level to a lower energy level it emits a photon, the energy of which is equal to the difference between the two energy levels. Chemistry A definite fixed energy that a molecule, atom, electron, or nucleus can have. In an atom, for example, the atom has a fixed energy corresponding to the orbitals in which its electrons move around the nucleus. The atom can accept a quantum of energy to become an excited atom (see excitation) if that extra energy will raise an electron to a permitted orbital. Between the ground state, which is the lowest possible energy level for a particular system, and the first excited state there are no permissible energy levels. According to the quantum theory, only certain energy levels are possible. An atom passes from one energy level to the next without passing through fractions of that energy transition. These levels are usually described by the energies associated with the individual electrons in the atoms, which are always lower than an arbitrary level for a free electron. The energy levels of molecules also involve quantized vibrational and rotational motion.
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