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--- exercises:common:sgcp [2025/06/19 02:34] – [4. How to Set Up in CP2K] jglan
+++ exercises:common:sgcp [2025/06/19 02:54] (current) – [2. Comparison with CPMD and BOMD] jglan
@@ Line 26: / Line 26: @@
 | Feature                          | CPMD          | BOMD         | SGCP                |
-| SCF at each step                 |  No          |  Yes        |  Partially (predictor-corrector) |
+| SCF at each step                 | No          | Yes        |  Partially (predictor-corrector) |
 | Time step                        | Small (~0.1 fs) | Large (~1 fs) | Large (~1–2 fs)           |
 | Conserved quantity preservation  | Excellent     | Reasonable   | Excellent                 |
@@ Line 69: / Line 69: @@
 ====4. How to Set Up in CP2K====
-### 1. ASPC Extrapolation
-```
+| Parameter              | Purpose                                  | Notes                                      |
-&FORCE_EVAL
+| EXTRAPOLATION_ORDER  | Higher gives better predictor            | 1–4 typical, 0 for metallic is more stable                               |
-  &DFT
+| MAX_SCF_HIST        | Controls SCF correction                  | ≥2 helps smoother convergence              |
-    &QS
+| STEPSIZE             | Time step in fs                          | ~0.5–2 fs depending on system                |
-      EXTRAPOLATION ASPC
+| PRECONDITIONER       | Affects SCF convergence                  | `FULL_SINGLE_INVERSE` slightly better      |
-      EXTRAPOLATION_ORDER 1
+| NOISY_GAMMA (γ_D)    | ASPC dissipation compensation            | Adjust to control drift in T and energy    |
-    &END QS
+| GAMMA (γ_L)          | Langevin thermostat strength             | Set to 0 for dissipation-only integration  |
-    &SCF
-      MAX_SCF_HIST 2
-    &END SCF
-  &END DFT
-&END FORCE_EVAL
-```
-### 2. Langevin Thermostat
+. ASPC Extrapolation
-```
+  &FORCE_EVAL
-&MOTION
+    &DFT
-  &MD
+       &QS
-    ENSEMBLE LANGEVIN
+        EXTRAPOLATION ASPC
-    &LANGEVIN
+        EXTRAPOLATION_ORDER 0 # Higher gives better corrector
-      GAMMA 0.005         ! γ_L
+       &END QS
-      NOISY_GAMMA 4.0E-4  ! γ_D
+       &SCF
-    &END LANGEVIN
+        MAX_SCF_HIST 2
-  &END MD
+       &END SCF
-&END MOTION
+    &END DFT
-```
+  &END FORCE_EVAL
-### 3. Atom-Specific γ_D (Optional)
+. Langevin Thermostat
+  &MOTION
+    &MD
+      ENSEMBLE LANGEVIN
+      &LANGEVIN
+        GAMMA 0.005         ! γ_L
+        NOISY_GAMMA 4.0E-4  ! γ_D
+      &END LANGEVIN
+    &END MD
+  &END MOTION
+. Atom-Specific γ_D (Optional)
+  &THERMAL_REGION
+    DO_LANGEVIN_DEFAULT TRUE
+    &DEFINE_REGION
+      TEMPERATURE 500
+      NOISY_GAMMA_REGION 4.E-4
+      LIST 577..745
+    &END DEFINE_REGION
+  &END THERMAL_REGION
-```fortran
-&THERMAL_REGION
-  DO_LANGEVIN_DEFAULT TRUE
-  &DEFINE_REGION
-    TEMPERATURE 500
-    NOISY_GAMMA_REGION 4.E-4
-    LIST 577..745
-  &END DEFINE_REGION
-&END THERMAL_REGION
-```