# Hybridisation in phosphorus allotropes

The white phosphorus has a tetrahedral structure, like this:

[Image source: Wikipedia]

The red phosphorus, on the other hand, has a polymeric structure:

For tetrahedral $\ce{P_4}$ in white phophorus, we can take $\ce{sp^3}$ hydbridisation, but some sites give information that P atom uses atomic 3p orbitals, as then the the angle strain is reduced from $\ce{109^\circ\rightarrow 60^\circ}$ to $\ce{90^\circ\rightarrow 60^\circ}$.