Difference Between Excitation and Absorption

Thekey differencebetween excitation and absorption is thatexcitation is the process of absorbing aphotonand moving into a higher energy level whereas absorption is the process of transferring energy from a photon to a certain object.

The terms absorption and excitation are useful in the fields ofquantum mechanics，分析化学，相对论等。您需要对这些术语有很好的理解，以正确理解这些字段的内容。吸收和激发的概念也是光谱和光谱法领域的基础概念。

内容

1.Overview and Key Difference
2.What is Excitation
3.What is Absorption
4.Side by Side Comparison – Excitation vs Absorption in Tabular Form
5.概括

什么是兴奋？

Excitation is the transfer of a system that is at a low energy state to a state of high energy. Thus, this term can be discussed regarding an electron bound to the nucleus at the基态. Quantum mechanics suggests that an electron can only take specific energy states. Furthermore, the probability of finding an electron in between these stationary states is zero. Therefore, the energy differences between the two stages are discrete values. That means; an electron can absorb or emit energies corresponding to any difference between stationary states, but not in between.

Excitation is the process of absorbing such a photon to go up to a higher energy level. The opposite process of excitation is emitting a photon to come down to a lower energy level. If the energy of the incident photon is sufficiently large enough, the electron will move to a very large energy state, thus removing itself from the atom. We call it “ionization”.

What is Absorption?

吸收是我们通常用来识别一些数量成为另一个数量的一部分的术语。在化学方面，我们主要使用术语吸收electromagnetic waves. The absorption of electromagnetic waves refers to the transferring process of the energy of the photon to the system in which the photon has been absorbed. In the process of absorption, the incident photon is lost.

Let us take a system with a single electron bound to the nucleus. For example, assume that the electron is in the ground state. If a photon collides with the electron, the electron can absorb the photon depending on the energy of the photon. Moreover, if the energy of the photon is equal to the energy difference between the ground state and some other state, the electron can absorb the photon. However, if the energy of the photon is not equal to an energy gap, the photon will not be absorbed. The photon has initial momentum due to the mass of the photon. It causes a momentum change of the electron when the photon is absorbed. Absorption is the major principle of the absorption and emission spectra.

What is the Difference Between Excitation and Absorption?

Excitation is the change of the state of a system to a state of higher energy while absorption is the energy transfer from a photon to a system. Hence, the key difference between excitation and absorption is that excitation is the process of absorbing a photon and moving into a higher energy level whereas absorption is the process of transferring energy from a photon to a certain object.

此外，为了激发，必须发生吸收，并且要吸收，必须激发系统。因此，吸收和激发是相互过程。

概括– Excitation vs Absorption

Excitation and absorption are closely related terms. The key difference between excitation and absorption is that excitation is the process of absorbing a photon and moving into a higher energy level whereas absorption is the process of transferring energy from a photon to a certain object.

Reference:

1.“激发。”。2006年8月17日Available here.

Image Courtesy:

1.乔丹·莱文（Jordan Levine）的“通过辐射激发能量水平（图）” - 自己的工作(CC BY-SA 4.0)viaCommons Wikimedia
2.“类胡萝卜素吸收光谱”byr7（CC由2.0）viaFlickr