wyckoffs:
- "f"
- "f"
- "f"
- "f"
- "b"
- "c"
- "b"
- "c"
- "i"
- "i"
- "i"
- "i"
- "i"
- "i"
- "i"
- "i"
- "i"
- "i"
- "i"
- "i"