The white phosphorus has a tetrahedral structure, like this:
[Image source: Wikipedia]
The red phosphorus, on the other hand, has a polymeric structure:
[Image source: google images]
Then what is the hybridisation state of P atoms in these allotropes?
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 $\ce{90^\circ\rightarrow 60^\circ}$.
I can't find any website which gives information about the hybridisation state of red phosphorus. My chemistry textbook also does not give any information about this.
If you can give a reference to back up your answer, it would be useful to me.
