diff --git a/source/source_esolver/esolver_fp.h b/source/source_esolver/esolver_fp.h
index 501bef9b68..74928c0bb2 100644
--- a/source/source_esolver/esolver_fp.h
+++ b/source/source_esolver/esolver_fp.h
@@ -9,6 +9,7 @@
 #include "source_estate/elecstate.h" // electronic states
 #include "source_estate/module_charge/charge_extra.h" // charge extrapolation
 #include "source_hamilt/module_surchem/surchem.h" // solvation model
+#include "source_pw/module_pwdft/parallel_grid.h" // Parallel_Grid (value member below)
 #include "source_pw/module_pwdft/vl_pw.h" // local pseudopotential
 #include "source_pw/module_pwdft/structure_factor.h" // structure factor
 
diff --git a/source/source_hamilt/module_surchem/cal_pseudo.cpp b/source/source_hamilt/module_surchem/cal_pseudo.cpp
index e58024d441..6a1547ddd3 100644
--- a/source/source_hamilt/module_surchem/cal_pseudo.cpp
+++ b/source/source_hamilt/module_surchem/cal_pseudo.cpp
@@ -1,5 +1,7 @@
 #include "surchem.h"
 
+#include "source_pw/module_pwdft/structure_factor.h" // Structure_Factor member access (sf->strucFac)
+
 // atom_in surchem::GetAtom;
 
 void surchem::gauss_charge(const UnitCell& cell,
diff --git a/source/source_hamilt/module_surchem/surchem.h b/source/source_hamilt/module_surchem/surchem.h
index c792414ca6..ae1a7db6bb 100644
--- a/source/source_hamilt/module_surchem/surchem.h
+++ b/source/source_hamilt/module_surchem/surchem.h
@@ -6,8 +6,10 @@
 #include "source_base/matrix.h"
 #include "source_basis/module_pw/pw_basis.h"
 #include "source_cell/unitcell.h"
-#include "source_pw/module_pwdft/parallel_grid.h"
-#include "source_pw/module_pwdft/structure_factor.h"
+
+// forward-declared: used below only as pointer/reference
+class Parallel_Grid;
+class Structure_Factor;
 
 class surchem
 {
diff --git a/source/source_pw/module_pwdft/forces.cpp b/source/source_pw/module_pwdft/forces.cpp
index 2f2e1ea3a8..386785cf9c 100644
--- a/source/source_pw/module_pwdft/forces.cpp
+++ b/source/source_pw/module_pwdft/forces.cpp
@@ -17,6 +17,7 @@
 #include "source_estate/module_pot/gatefield.h"
 #include "source_hamilt/module_ewald/H_Ewald_pw.h"
 #include "source_hamilt/module_surchem/surchem.h"
+#include "source_pw/module_pwdft/structure_factor.h" // Structure_Factor member access (p_sf->strucFac)
 #include "source_hamilt/module_vdw/vdw.h"
 
 #ifdef _OPENMP
diff --git a/source/source_pw/module_pwdft/hamilt_pw.h b/source/source_pw/module_pwdft/hamilt_pw.h
index 958f82c8e3..ee7d228087 100644
--- a/source/source_pw/module_pwdft/hamilt_pw.h
+++ b/source/source_pw/module_pwdft/hamilt_pw.h
@@ -4,7 +4,6 @@
 #include "source_base/kernels/math_kernel_op.h"
 #include "source_base/macros.h"
 #include "source_cell/klist.h"
-#include "source_esolver/esolver_ks_pw.h"
 #include "source_estate/module_pot/potential_new.h"
 #include "source_hamilt/hamilt.h"
 #include "source_lcao/module_dftu/dftu.h" // mohan add 2025-11-06