# MODE_SELECTIVE

All parameters needed for to run a mode selective vibrational analysis. The keywords FREQUENCY, RANGE, and the subsection INVOLVED_ATOMS are mutually exclusive. [Edit on GitHub]

Subsections

- INVOLVED_ATOMS
- PRINT

## Keywords

- ATOMS

- EPS_MAX_VAL

- EPS_NORM

- FREQUENCY

- INITIAL_GUESS

- LOWEST_FREQUENCY

- RANGE

- RESTART_FILE_NAME

## Keyword descriptions

ATOMS: integer[ ]

  Usage: ATOMS {integer} {integer} .. {integer}

  Specifies the list of atoms which should be displaced for the Initial guess [Edit on GitHub]

EPS_MAX_VAL: real = 5.00000000E-007

  Usage: EPS_MAX_VAL {REAL}

  Convergence criterion for the davidson algorithm. Specifies the maximal value in the residuum vectors [Edit on GitHub]

EPS_NORM: real = 2.00000000E-006

  Usage: EPS_NORM {REAL}

  Convergence criterion for the davidson algorithm. Specifies the maximal value of the norm of the residuum vectors [Edit on GitHub]

FREQUENCY: real = -1.00000000E+000

  Usage: FREQUENCY {REAL}

  value close to the expected value of the frequency to look for. If the block Davidson algorithm is applied, the nrep closest frequencies are tracked. [Edit on GitHub]

INITIAL_GUESS: enum = ATOMIC

  Usage: INITIAL_GUESS BFGS_HESS

  Valid values:

  - `BFGS_HESS` get the first displacement vector out of the BFGS approximate Hessian

  - `ATOMIC` use random displacements for a set of atoms specified

  - `RESTART` use data from MS_RESTART as initial guess

  - `RESTART_VEC` use a vector from MS_RESTART, useful if you want to increase accurcy by changing functionals or basis

  - `MOLDEN_RESTART` use the .mol file of a former run, to restart a vector (similar to Restart_vec, but a different file FORMAT is used)

  The type of initial guess for the normal modes [Edit on GitHub]

LOWEST_FREQUENCY: real = 0.00000000E+000

  Usage: LOWEST_FREQUENCY <REAL>

  Lowest frequency mode to include when writing output. Use a negative value to print imaginary frequencies. Useful for visualizing the imaginary frequency along a reaction path coordinate Depending on accuracy settings, the output might include spurious low frequency imaginary modes which should be visually checked (see MOLDEN_VIB). [Edit on GitHub]

RANGE: real[ ]

  Usage: RANGE {REAL} {REAL}

  Track modes in a given range of frequencies. No warranty that the set of frequencies is complete. [Edit on GitHub]

RESTART_FILE_NAME: string

  Usage: RESTART_FILE_NAME {filename}

  Specifies the name of the file used to create the restarted vectors [Edit on GitHub]