Update README.md

README.md

@@ -3,21 +3,39 @@
 This is python code of generating MP2, MP3, and MP4 correlation energy density based on **one boby decomposition scheme** (https://doi.org/10.1002/qua.22017)
 
 Requirement of python packages:
-```python
+```shell
 numpy, scipy, h5py, torch, quadpy, itertools, mmap, tqdm
 ```
 Optional of python packages:
-```python
-pycuda, skcuda #if you use GPU for preparing Ajb
+```shell
+pycuda, skcuda # if you use GPU for preparing Ajb
+```
+Requirement of external packages:
+```shell
+Psi4 # to generate wavefunction and FCIDUMP file
+molden2aim # to convert molden format to .WFN
 ```
 
+
 ## Examples
 ### ch4_200_031
-This is to calculate energy dnsity on Carbon and Hydrogen atom of CH4 with grid settings:
+This is to calculate energy density on Carbon and Hydrogen atom of CH4@3-21g with grid settings:
 Legendre quadrature (200 radial points) and Lebedev quadrature (noted as 031, 350 angular points).
 
 ```shell
-# cd ch4_200_031/
+# prepare wavefunction and FCIDUMP files, here we use Psi4 package
+cd examples/ch4_200_031/calcu/
+psi4 -n 8 -i input.dat -o output.dat
+
+# convert molden format of wavefunction and txt format of FCIDUMP (in Psi 4 is INPDUMP)
+# into .npy files
+# Note that external package is needed to convert molden to .WFN first, we use molden2aim 
+# (https://github.com/zorkzou/Molden2AIM) for example.
+cd ../prep/
+chmod +x mlcorr_prep.sh
+./mlcorr_prep.sh ch4
+
+# 
 ```