I've heard molecules are constantly moving or vibrating. What is the mechanism behind this? Where does the energy come from, and go? Is it always a function of temperature/pressure?
nuby said:What is the mechanism behind this?
Where does the energy come from, and go?
Is it always a function of temperature/pressure?
The mechanism behind molecular vibrations is the movement of atoms within a molecule, which is caused by the interaction of the atoms' nuclei and electrons. This movement is driven by the energy stored in chemical bonds.
The primary source of energy for molecular vibrations is the absorption of infrared (IR) radiation. When IR radiation is absorbed by a molecule, it causes the bonds between atoms to stretch and bend, resulting in molecular vibrations.
Molecular vibrations can be detected through various spectroscopic techniques, such as infrared spectroscopy, Raman spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. These techniques measure the absorption or emission of radiation by the molecule, which can provide information about its vibrational modes.
Molecular vibrations can affect various properties of a molecule, including its shape, bond strength, and reactivity. For example, changes in the vibrational energy of a molecule can lead to changes in its bond lengths and angles, which can affect its overall shape and stability.
Molecular vibrations play a crucial role in chemical reactions by providing the necessary energy for bonds to break and form. Vibrational energy can also affect the rate of a reaction, as molecules with higher vibrational energy are more likely to collide and react with other molecules.