Key Derivation
Two keys are needed to create a silent payments address: the spend key and the scan key. To ensure compatibility, wallets MAY use BIP32 derivation with the following derivation paths for the spend and scan key. When using BIP32 derivation, wallet software MUST use hardened derivation[19] for both the spend and scan key.
A scan and spend key pair using BIP32 derivation are defined (taking inspiration from BIP44) in the following manner:
scan_private_key: m / purpose' / coin_type' / account' / 1' / 0
spend_private_key: m / purpose' / coin_type' / account' / 0' / 0
purpose is a constant set to 352 following the BIP43 recommendation. Refer to BIP43 and BIP44 for more details.