docs: fix spelling typos in system guides (#966)

Problem
- Several system guide pages contain obvious spelling mistakes.
- The typos scan also reports issues in sample output files, which
should not be edited as documentation typos.

Change
- Fix spelling mistakes in BondOrderSystem, System, and MultiSystems
docs
- Leave sample output files untouched to avoid false-positive edits

Notes
- Docs-only change

Authored by OpenClaw (model: gpt-5.4)


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

## Documentation
* Corrected spelling, grammar, and terminology errors throughout system
documentation to improve overall clarity and accuracy. Updates address
multiple typographical mistakes, refine phrasing for enhanced
consistency, and clarify technical descriptions. These improvements
ensure users have access to more reliable and readable guidance for
better understanding of system operations, features, and configurations.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Author: njzjz-bot

docs/systems/bond_order_system.md

@@ -32,8 +32,8 @@ system = dpdata.BondOrderSystem(rdkit_mol=mol)
 The {class}`BondOrderSystem <dpdata.BondOrderSystem>` implements a more robust sanitize procedure for rdkit Mol, as defined in {class}`dpdata.rdkit.santizie.Sanitizer`. This class defines 3 level of sanitization process by: low, medium and high. (default is medium).
 
 - low: use `rdkit.Chem.SanitizeMol()` function to sanitize molecule.
-- medium: before using rdkit, the programm will first assign formal charge of each atom to avoid inappropriate valence exceptions. However, this mode requires the rightness of the bond order information in the given molecule.
-- high: the program will try to fix inappropriate bond orders in aromatic hetreocycles, phosphate, sulfate, carboxyl, nitro, nitrine, guanidine groups. If this procedure fails to sanitize the given molecule, the program will then try to call `obabel` to pre-process the mol and repeat the sanitization procedure. **That is to say, if you wan't to use this level of sanitization, please ensure `obabel` is installed in the environment.**
+- medium: before using rdkit, the program will first assign formal charge of each atom to avoid inappropriate valence exceptions. However, this mode requires the rightness of the bond order information in the given molecule.
+- high: the program will try to fix inappropriate bond orders in aromatic heterocycles, phosphate, sulfate, carboxyl, nitro, nitrine, guanidine groups. If this procedure fails to sanitize the given molecule, the program will then try to call `obabel` to pre-process the mol and repeat the sanitization procedure. **That is to say, if you want to use this level of sanitization, please ensure `obabel` is installed in the environment.**
   According to our test, our sanitization procedure can successfully read 4852 small molecules in the PDBBind-refined-set. It is necessary to point out that the in the molecule file (mol/sdf), the number of explicit hydrogens has to be correct. Thus, we recommend to use
   `obabel xxx -O xxx -h` to pre-process the file. The reason why we do not implement this hydrogen-adding procedure in dpdata is that we can not ensure its correctness.
 
@@ -56,4 +56,4 @@ print(syst.get_formal_charges())  # return the formal charge on each atom
 print(syst.get_charge())  # return the total charge of the system
 ```
 
-If a valence of 3 is detected on carbon, the formal charge will be assigned to -1. Because for most cases (in alkynyl anion, isonitrile, cyclopentadienyl anion), the formal charge on 3-valence carbon is -1, and this is also consisent with the 8-electron rule.
+If a valence of 3 is detected on carbon, the formal charge will be assigned to -1. Because for most cases (in alkynyl anion, isonitrile, cyclopentadienyl anion), the formal charge on 3-valence carbon is -1, and this is also consistent with the 8-electron rule.

docs/systems/multi.md

@@ -1,6 +1,6 @@
 # `MultiSystems`
 
-The Class {class}`dpdata.MultiSystems` can read data from a dir which may contains many files of different systems, or from single xyz file which contains different systems.
+The Class {class}`dpdata.MultiSystems` can read data from a dir which may contains many files of different systems, or from a single xyz file that contains different systems.
 
 Use {meth}`dpdata.MultiSystems.from_dir` to read from a directory, {class}`dpdata.MultiSystems` will walk in the directory
 Recursively and find all file with specific file_name. Supports all the file formats that {class}`dpdata.LabeledSystem` supports.
@@ -26,11 +26,11 @@ vasp_multi_systems = dpdata.MultiSystems.from_dir(
     dir_name="./mgal_outcar", file_name="*OUTCAR", fmt="vasp/outcar"
 )
 
-# print the multi_system infomation
+# print the multi_system information
 print(xyz_multi_systems)
 print(xyz_multi_systems.systems)  # return a dictionaries
 
-# print the system infomation
+# print the system information
 print(xyz_multi_systems.systems["B1C9"].data)
 
 # dump a system's data to ./my_work_dir/B1C9_raw folder
@@ -40,7 +40,7 @@ xyz_multi_systems.systems["B1C9"].to_deepmd_raw("./my_work_dir/B1C9_raw")
 xyz_multi_systems.to_deepmd_raw("./my_deepmd_data/")
 ```
 
-You may also use the following code to parse muti-system:
+You may also use the following code to parse multi-system:
 
 ```python
 from dpdata import LabeledSystem, MultiSystems
@@ -49,7 +49,7 @@ from glob import glob
 """
 process multi systems
 """
-fs = glob("./*/OUTCAR")  # remeber to change here !!!
+fs = glob("./*/OUTCAR")  # remember to change here !!!
 ms = MultiSystems()
 for f in fs:
     try:

docs/systems/system.md

@@ -6,7 +6,7 @@ This section gives some examples on how dpdata works. Firstly one needs to impor
 import dpdata
 ```
 
-The typicall workflow of `dpdata` is
+The typical workflow of `dpdata` is
 
 1. Load data from vasp or lammps or deepmd-kit data files.
 1. Manipulate data
@@ -108,7 +108,7 @@ dpdata.System("./POSCAR").replicate(
 )
 ```
 
-tuple(1,2,3) means don't copy atom configuration in x direction, make 2 copys in y direction, make 3 copys in z direction.
+tuple(1,2,3) means don't copy atom configuration in x direction, make 2 copies in y direction, make 3 copies in z direction.
 
 ### perturb
 
@@ -126,7 +126,7 @@ print(perturbed_system.data)
 
 ### replace
 
-By the following example, Random 8 Hf atoms in the system will be replaced by Zr atoms with the atom postion unchanged.
+By the following example, Random 8 Hf atoms in the system will be replaced by Zr atoms with the atom position unchanged.
 
 ```python
 s = dpdata.System("tests/poscars/POSCAR.P42nmc", fmt="vasp/poscar")