ABINIT Discussion Forums

Hello,

I'd like to get dynamical matrix in cartesian coordinate not just phonon frequencies from RF code.
If anyone knows, can you please let me know what's the unit of dynamical matrix (cartesian coordinate) in output file of RF calculation? Is it eV/ang^2 or Ha/bohr^2?
Also, does it include mass?

Below is from output file of RF code. Thank you!

----------------------
Dynamical matrix, in cartesian coordinates,
if specified in the inputs, asr has been imposed
j1 j2 matrix element
dir pert dir pert real part imaginary part

1 1 1 1 0.0172048238 0.0000000000
1 1 2 1 0.0000000000 0.0000000000
1 1 3 1 0.0000000000 0.0000000000
1 1 1 2 -0.0172040444 0.0000000000
1 1 2 2 0.0000000000 0.0000000000
1 1 3 2 0.0000000000 0.0000000000

2 1 1 1 0.0000000000 0.0000000000
2 1 2 1 0.0172048238 0.0000000000
2 1 3 1 0.0000000000 0.0000000000
2 1 1 2 0.0000000000 0.0000000000
2 1 2 2 -0.0172040444 0.0000000000
2 1 3 2 0.0000000000 0.0000000000

3 1 1 1 0.0000000000 0.0000000000
3 1 2 1 0.0000000000 0.0000000000
3 1 3 1 0.0378066618 0.0000000000
3 1 1 2 0.0000000000 0.0000000000
3 1 2 2 0.0000000000 0.0000000000
3 1 3 2 -0.0378068032 0.0000000000

1 2 1 1 -0.0172040444 0.0000000000
1 2 2 1 0.0000000000 0.0000000000
1 2 3 1 0.0000000000 0.0000000000
1 2 1 2 0.0172048238 0.0000000000
1 2 2 2 0.0000000000 0.0000000000
1 2 3 2 0.0000000000 0.0000000000

2 2 1 1 0.0000000000 0.0000000000
2 2 2 1 -0.0172040444 0.0000000000
2 2 3 1 0.0000000000 0.0000000000
2 2 1 2 0.0000000000 0.0000000000
2 2 2 2 0.0172048238 0.0000000000
2 2 3 2 0.0000000000 0.0000000000

3 2 1 1 0.0000000000 0.0000000000
3 2 2 1 0.0000000000 0.0000000000
3 2 3 1 -0.0378068032 0.0000000000
3 2 1 2 0.0000000000 0.0000000000
3 2 2 2 0.0000000000 0.0000000000
3 2 3 2 0.0378066618 0.0000000000

Hello,

After calculating phonon frequency and comparing with experimental value, unit of the dynamical matrix (in cartesian) in the output file seems Ha/bohr^2.
And, it seems not contain mass.

correct - abinit always has everything in Hartree atomic units (unless explicitly specified).

The DDB file (I presume you are referring to this data) contains the second derivatives of the energy.