Struct GediisOptimizer 

pub struct GediisOptimizer {
    pub config: GediisConfig,
    pub rise_tracker: EnergyRiseTracker,
}

Main GEDIIS optimizer.

Fields

config: GediisConfig

Configuration

rise_tracker: EnergyRiseTracker

Energy rise tracker

Implementations

impl GediisOptimizer

pub fn new() -> Self

Creates a new GEDIIS optimizer with default configuration.

pub fn with_config(config: GediisConfig) -> Self

Creates a new GEDIIS optimizer with specified configuration.

pub fn select_variant( &self, rms_error: f64, energy_rises: bool, n_points: usize, energies: Option<&VecDeque<f64>>, ) -> GediisVariant

Selects the appropriate GEDIIS variant based on optimization state.

Implements the decision logic from Old Code GeoDIS:

• OKEnD requires NGDIIS >= 4 for TS search, >= 2 for minimum
• OKEnD also requires |DC| >= SmlDif where DC = E(1) - E(2)
• EnDIS used when RMSErr > SimSw or energy rises

pub fn compute_step( &mut self, coords: &VecDeque<DVector<f64>>, grads: &VecDeque<DVector<f64>>, energies: &VecDeque<f64>, quad_steps: Option<&VecDeque<DVector<f64>>>, ) -> Option<(DVector<f64>, Vec<f64>)>

Computes a GEDIIS step.

Arguments

• coords - History of coordinate vectors (Angstrom)
• grads - History of gradient vectors (Ha/Å)
• energies - History of energies (Ha)
• quad_steps - History of quadratic steps (optional, for RFO-DIIS)

Returns

Tuple of (new_coords, coefficients) or None if failed.

fn build_rfo_diis_matrix( &self, steps: &VecDeque<DVector<f64>>, n: usize, ) -> DMatrix<f64>

Builds RFO-DIIS matrix from quadratic steps.

A[i,j] = <q_i, q_j> For TS search, first coordinate is weighted by ts_scale.

fn build_energy_diis_matrix( &self, grads: &VecDeque<DVector<f64>>, coords: &VecDeque<DVector<f64>>, n: usize, ) -> DMatrix<f64>

Builds Energy-DIIS matrix.

Trace: AMTrc[i,j] = -<g_i, x_j> A[i,j] = AMTrc[i,i] + AMTrc[j,j] - AMTrc[i,j] - AMTrc[j,i]

For TS search (n_neg > 0), the first coordinate is weighted by ts_scale to emphasize the reaction coordinate, matching Old Code: AMTrc(I+1,J+1) = -SclDIS*ANFF(1,I)*ANCC(1,J) - SProd(NVarT-1,ANFF(2,I),ANCC(2,J))

fn build_sim_diis_matrix( &self, grads: &VecDeque<DVector<f64>>, coords: &VecDeque<DVector<f64>>, _energies: &VecDeque<f64>, n: usize, quad_steps: Option<&VecDeque<DVector<f64>>>, ) -> DMatrix<f64>

Builds Simultaneous-DIIS matrix.

Combines Energy-DIIS with quadratic energy approximation. Formula: A[i,j] = EnDIS[i,j] + 0.5*(q_i·f_i + q_j·f_j) where q = quadratic step and f = forces (negative gradient).

This matches the Old Code GeoDIS implementation: Half*(SProd(NVarT,AQuad(1,I),ANFF(1,I)) + SProd(NVarT,AQuad(1,J),ANFF(1,J)))

Trait Implementations

impl Default for GediisOptimizer

fn default() -> Self

Returns the “default value” for a type.