diff --git a/src/ctrl_io/mod.rs b/src/ctrl_io/mod.rs
index fcd15c008f76fd15911963c02a4243217fe7bac6..67935f33cc7ea17526bf20a97e4c5d1327162dd2 100644
--- a/src/ctrl_io/mod.rs
+++ b/src/ctrl_io/mod.rs
@@ -11,13 +11,13 @@ use crate::analdrv::config::{AnalDrvConfig, AnalDrvTask};
 use crate::ctrl_io::tddft_parameters::parse_tddft_keywords;
 use crate::ctrl_io::hessian_parameters::parse_hessian_keywords;
 use crate::ctrl_io::thermo_parameters::parse_thermo_keywords;
-use crate::{check_norm::force_state_occupation::ForceStateOccupation};
+use crate::{scf_io::force_state_occupation::ForceStateOccupation};
 use crate::scf_io::smear::SmearingType;
 use crate::dft::{DFAFamily, DFTType};
 use crate::geom_io::{GeomCell, MOrC, parse_geom_keywords};
 use crate::utilities;
 // use rayon::ThreadPoolBuilder;
-use crate::check_norm::OCCType;
+use crate::scf_io::occupation::OCCType;
 use tensors::matrix_blas_lapack::{omp_set_num_threads_wrapper};
 use crate::solvent::{PcmMethod, RadiusScheme};
 use crate::x2c::RelativisticMethod;
diff --git a/src/initial_guess/sad.rs b/src/initial_guess/sad.rs
index afe9b9ab466d4b898febc41369989c9f04c26d1f..f9a83ca8e9037fc052b7a4f6f8429b461ffbb530 100644
--- a/src/initial_guess/sad.rs
+++ b/src/initial_guess/sad.rs
@@ -1,5 +1,5 @@
 use tensors::{MatrixFull, BasicMatrix};
-use crate::check_norm::OCCType;
+use crate::scf_io::occupation::OCCType;
 use crate::molecule_io::Molecule;
 use crate::ctrl_io::InputKeywords;
 use crate::geom_io::{GeomCell, formated_element_name};
diff --git a/src/lib.rs b/src/lib.rs
index 7c57f09dd041d58ba81172a81aba0f9d85982b8a..984ddd19385f0d2c5973a675092aa042250f5688 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -57,7 +57,6 @@ extern crate anyhow;
 extern crate lazy_static;
 pub mod basis_io;
 pub mod constants;
-pub mod check_norm;
 pub mod ctrl_io;
 pub mod dft;
 pub mod geom_io;
diff --git a/src/check_norm/force_state_occupation.rs b/src/scf_io/force_state_occupation.rs
similarity index 100%
rename from src/check_norm/force_state_occupation.rs
rename to src/scf_io/force_state_occupation.rs
diff --git a/src/scf_io/mod.rs b/src/scf_io/mod.rs
index 7cd507a0aace3bd62cbe1b8c1881cff0baac94f8..f49a3fe40820cbd9a5c53817b445351839d8d533 100644
--- a/src/scf_io/mod.rs
+++ b/src/scf_io/mod.rs
@@ -1,7 +1,7 @@
 #![warn(unused_imports)]
 use crate::basis_io::ecp::ghost_effective_potential_matrix;
-use crate::check_norm::force_state_occupation::adapt_occupation_with_force_projection;
-use crate::check_norm::{self, generate_occupation_frac_occ, generate_occupation_integer, generate_occupation_sad, OCCType};
+use self::force_state_occupation::adapt_occupation_with_force_projection;
+use self::occupation::{generate_occupation_frac_occ, generate_occupation_integer, generate_occupation_sad, OCCType};
 use crate::dft::gen_grids::prune::prune_by_rho;
 use crate::dft::{DFTType, Grids};
 use crate::geom_io::{calc_nuc_energy, calc_nuc_energy_with_ext_field, calc_nuc_energy_with_point_charges};
@@ -19,6 +19,8 @@ mod pyrest_scf_io;
 pub mod scfrecord;
 pub mod smear;
 pub mod util;
+pub mod occupation;
+pub mod force_state_occupation;
 
 #[cfg(feature = "mpi")]
 use mpi::collective::SystemOperation;
@@ -5269,7 +5271,7 @@ pub fn scf_without_build(scf_data: &mut SCF, mpi_operator: &Option<MPIOperator>)
     }
     match scf_data.mol.ctrl.occupation_type {
         OCCType::FRAC => {
-            let (occupation, homo, lumo) = check_norm::generate_occupation_integer(&scf_data.mol, &scf_data.scftype);
+            let (occupation, homo, lumo) = occupation::generate_occupation_integer(&scf_data.mol, &scf_data.scftype);
             scf_data.occupation = occupation;
             scf_data.homo = homo;
             scf_data.lumo = lumo;
diff --git a/src/check_norm/mod.rs b/src/scf_io/occupation.rs
similarity index 99%
rename from src/check_norm/mod.rs
rename to src/scf_io/occupation.rs
index dc1370d55ecad6b3686c38f65f0f25e7cac28c2b..ae1b1a59e182eda05198705a906725d1238d9699 100644
--- a/src/check_norm/mod.rs
+++ b/src/scf_io/occupation.rs
@@ -11,8 +11,6 @@ pub enum OCCType {
     ATMSAD,
 }
 
-pub mod force_state_occupation;
-
 pub fn generate_occupation_frac_occ(mol: &Molecule, scftype: &SCFType, eigenvalues: &[Vec<f64>;2], tolerant: f64) -> ([Vec<f64>;2],[usize;2],[usize;2]) {
     let num_state = mol.num_state;
     let spin_channel = mol.ctrl.spin_channel;