Performs a gradient calculation. This command can appear in the global context.

### Options

engrad_file

Save the gradients in GROMACS format in the named file.

• The type is string
• There is no default value.
incore

Flag for whether to construct the response matrix explicitly.

• The type is bool
• The default is false
• The value must be one of:
• true - Construct the response matrix explicitly and store it in memory. This option is only available for response calculations based on a Hartree-Fock wavefunction, and should be used only for testing purposes.
• false - Do not construct the response matrix explicitly, but compute the matrix-vector product instead. This will require iterative solvers.
load_transition_density

Load the AO transition density matrix from file (in arma::arma_binary) format.

• The type is string
• There is no default value.
name

Specify the name of a set of results.

This option is deprecated.

• The type is string
• There is no default value.
numerical

Flag for whether to compute the gradient analytically.

• The type is bool
• The default is false
• The value must be one of:
• false - Compute gradient analytically.
• true - Compute gradient numerically using finite difference.
print_level

Print level.

• The type is int
• There is no default value.
• The value must be one of:
• -2 - No output
• -1 - Minimum output
• 0 - Output that doesn't scale with system size
• 1 - Output that scales linearly with system size
• 2 - (Debugging) output that scales quadratically with system size
• 3 - (Debugging) output that scales cubically with system size
save_transition_density

Save the AO transition density matrix to file (in arma::arma_binary) format.

• The type is string
• There is no default value.
step_size

Specify the step size for numerical differentiation.

• The type is quantity
• The default is 1e-3 bohr
• The value must be positive
tighter_scf

Flag for whether to use tighter SCF convergence thresholds than those specified in dft or emft. If true, set orbital_grad_threshold 10 times smaller than specified, and energy_threshold 100 times smaller than specified.

• The type is bool
• The default is false