Are you sure that you have that right? a.u. usually refers to the Astronomical Unit, which is a measure of distance (I can't remember the exact conversion factor, but I'm sure its of the order of 109m).El Flea said:Does anyone knows what this unit "a.u" means? I found it on many graphs, where "a.u" represents the unit of |E|^2 (E represents electromagnetic field). How do I convert "a.u" to SI unit?
Well I never knew that! You learn something new every day, thanks jtbell.jtbell said:I suspect it means "arbitrary unit", that is, no particular unit at all. In this case those graphs are intended to show only the relative values of E^2 at different points on the graph, without regard for the overall scale.
The unit 'a.u.' stands for atomic units and it is a system of measurement used in atomic physics. It is defined as a set of units that simplifies calculations involving the properties of atoms and molecules.
The unit 'a.u.' is commonly used in quantum mechanics and other atomic and molecular physics calculations. It is also used in chemistry, materials science, and other fields that involve the study of atoms and molecules.
The basic units of the 'a.u.' system are the atomic mass unit (amu) for mass, the Bohr radius for length, the electronvolt for energy, and the atomic unit of time for time.
To convert from 'a.u.' to SI units, you can use conversion factors for each unit. For example, to convert energy from atomic units to joules, you can use the conversion factor of 1 a.u. = 4.35974434 × 10^-18 J.
Yes, an example of converting the 'a.u.' unit of length (Bohr radius) to SI units is as follows: 1 Bohr radius = 0.52917721067 Å (angstrom) 0.52917721067 Å x 1.889725989 Å = 1 a.u. Therefore, 1 a.u. = 0.52917721067 x 1.889725989 Å = 1.00000238 Å. Hence, 1 a.u. = 1.00000238 Å in SI units.