Drag-and-drop Raman peak fitting: BWF/asymmetric lineshapes, arPLS baselines, AIC/BIC/F-test model selection, bootstrap CIs, two-zone carbon workflow, and Origin export.

Drag-and-drop Raman peak fitting. Fit a spectrum, read its metrics, and send the results, ratios, fit statistics and graphs back to Origin.

Everyday workflow

1. Open the App on an active worksheet (X = Raman shift, Y = intensity) or a spectrum graph. Use Reload active Origin window after switching spectra.
2. Preprocess (optional): Despike, calibrate, IRF. Avoid smoothing before quantitative width/area work.
3. Baseline: arPLS (auto) or anchors, then Subtract → Peaks.
4. Place peaks: load a preset (carbon 1st-order / Sadezky, 2nd-order), + Add peak, or Find peaks. Drag the ? apex and ¦ side handles; reorder rows with ??.
5. Fit range: one window, or two zones (1st + 2nd order). Bands outside the active zone are held fixed.
6. Fit — Fit (Levenberg–Marquardt). Read reduced χ², R², AIC/BIC below the table.
7. Metrics: pick I(D)/I(G), I(2D)/I(G), … or build a custom ratio; set the laser λ for crystallite size L_a.
8. Validate / bootstrap: Validate fit (11 gates), Run bootstrap for confidence intervals.
9. Export: Send results to Origin — parameters, ratios, fit-statistics sheets and a fitted graph.

Two-zone carbon (1st + 2nd order)

1. Fit range → 1st order; place D/G (or Sadezky) bands; Fit.
2. Switch to 2nd order; add the overtone preset (D+D″, 2D (G′), D+G, 2D′); Fit again — first-order bands stay fixed.
3. All bands sit in one table; build cross ratios like I(2D)/I(G). Export writes a separate workbook + graph per zone.

If the window opens blank on the first launch of a session, click the App icon again. Closing with unsaved peaks warns you — use Save session or Send results to Origin first.