Chemiosmosis which isn’t related to is the production of ATP.
Chemiosmosis is the production of ATP inside the chloroplast.
Inside the chloroplast when ##H_2O## is split into 3 seperate components you get a 2 Hydrogen atoms. These Hydrogen atoms are left to float around inside the Chloroplast until they are used.
When they are used they are basically sucked up a protein called ATP Synthase. This movement of Hydrogen across the membrane produces ATP. This process is known as chemiosmosis.