Question: Units - defining units permanently for future use

hello how do i define new units of multiple units. so i am able to choose them inside the Choose Unit in the rigth side

because as you can see there are not an option to define this as Unit -> [J/(K*mol)]

instead i have the option to use [m^2*kg/(s^2*K*mol)]

because i seen that you can defijne and install new units i just dont know how to impliment it so they alway remember my new units without i am suposed to initialize it with a command at top of my script

ps i also dont know how to define my new unit an just run that command at top of my script either.

but it would be better if it is permanent installed

i ask because i have several other units that is trublesome in maple (being in chemistry, we dont always use SI units) so molar [M] is also some times trublesome

as mapleprime often ask if we can include code i will do that

write this formula

3/(2)*8.3144621*J*K^(-1)*mol^(-1)

and use the simplify command in the right side and see that the unit is

thx