Molecular excitation refers to the promotion of an electron to an excited state. This particular pheomenon is extremely important for current scientific discovery, particularly in the biological sciences.
As you go through the topic, you will learn about the different concepts that are involved with an excitation event. Simple harmonic motion, Morse potentials, and electromagnetic radiation are just some of the topics that will be covered.
At the end of this particular section, you will be introduced to what happens following molecular excitation. In particular, you will be introduced to molecular emission events when the topic of fluorescence is introduced.
As you proceed through this section you will be taught about:
See that panel to the left? That is where you be able to interact with the module. Be sure to explore these interactive modules as they can be a great asset in understanding the material presented.
Want a challenge?
While going through each of the topics, you can quickly test your knowledge by choosing to complete the Challenge questions. These short questions could help you recognize what you are having trouble understanding.
The faster you correctly answer these questions, the more points you will be awarded. The more points you are awarded, the quicker you will unlock other Avatars. See what Avatars are available by clicking on your avatar above.
To get started click the right arrow below or click on a topic of interest to the left.
You will see a brief description and will be given a chance to jump directly to that topic
This topic is not currently available.
Physical chemistry attempts to understand chemistry through the physical world and using instrumentation.
Molecular excitation refers to the promotion of an electron to an excited state. This particular pheomenon is extremely important for current scientific discovery, particularly in the biological sciences.
A simple harmonic oscillator displays a very particular type of periodic motion called simple harmonic motion. A common example of a simple harmonic oscillator is a spring that is compressed or stretched.
Morse potentials are used to model the interaction between two atoms in a diatomic molecule.
A diatomic molecule has only two atoms which are connected through a chemical bond. This particular diatomic molecule is double bonded.
The energy of a diatomic molecule can be approximated using a Morse Potential. Quantum effects are not discussed.
The vibrational state of the diatomic molecule refers to the frequency at which the atoms oscillate (ie. the bond stretches and compresses).
A single rotational mode is available to the diatomic molecule and involves rotation around an axis that is perpendicular to the bond axis. The energy of the rotational mode is directly related to its angular momentum.
Electromagnetic radiation is a form of that travels in waves. Specifically, electromagnetic energy travels in a transverse wave that oscillates at a certain frequency.
Like other dipoles, the transition dipole refers to a difference in charge from one location of a molecule to another. The transition dipole occurs when an electron is excited from the ground state to an excited state.
The Jablonski diagram is capable of showing the transition between ground states and excited states by using quantized Morse potentials.
Fluorescence begins with absorption and molecular excitation into an excited state. Once promoted, the electron will fall to the lowest vibrational energy within that excited state.