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fixed_blend_step

omecp::optimizer

Function fixed_blend_step 

Source 
pub fn fixed_blend_step(
    opt_state: &OptimizationState_blend,
    max_step: f64,
    thresh_rms_g: f64,
    print_level: usize,
    reduced_factor: f64,
    step_reduction_multiplier: f64,
) -> DVector<f64>
Expand description

Hybrid GEDIIS/GDIIS step.

Combines GDIIS_blend and GEDIIS_blend into one step with blend.

§Algorithm

Phase 1 — GDIIS:

  • Error vectors via inverted mean true Hessian
  • Newton correction on interpolated geometry

Phase 2 — EDIIS:

  • Taylor expansion B-matrix with energy RHS
  • Pure interpolation, NO Newton correction

Phase 3 — Hybrid blend :

x_new = (x_gdiis + x_ediis) / 2

Phase 4 — Step control:

  • Factor = 0.5 if ||F_hist|| < thresh_rms_g * 10
  • Step capped to max_step

§Arguments

  • opt_state - Optimization state with geometry, force, Hessian, and energy history.
  • max_step - Maximum allowed step size (maxstep).
  • thresh_rms_g - RMS gradient threshold (conver[4]).
  • reduced_factor - Step reduction factor when activated.

§Returns

The blended and step-controlled new geometry.