My level 7 Paladin(2)/Fighter(5) found a necklace of prayer beads. Can those spells bound to the beads be used for Divine Smite?
The relevant part of the paladin's Divine Smite feature description says (emphasis mine):
Starting at 2nd level, when you hit a creature with a melee weapon attack, you can expend one spell slot to deal radiant damage to the target, in addition to the weapon's damage. The extra damage is 2d8 for a 1st-level spell slot, plus 1d8 for each spell level higher than 1st, to a maximum of 5d8. [...]
The relevant part of the description of the necklace of prayer beads says (emphasis mine):
This necklace has 1d4 + 2 magic beads made from aquamarine, black pearl, or topaz. [...] Each bead contains a spell that you can cast from it as a bonus action (using your spell save DC if a save is necessary). Once a magic bead's spell is cast, that bead can't be used again until the next dawn.
Divine Smite explicitly talks of spell slots, while the necklace of prayer beads does not, although the functionality of the beads is quite similar. So from my understanding, using beads in place of spell slots is not intended.
Can a Paladin expend beads from the necklace of prayer beads to use the Divine Smite feature?