The atomic and electronic structure of amorphous BP4

► There is no investigation on the structure of the amorphous BPx film by calculation. ► We use MD combined with experiment to reveal the microstructure of amorphous BPx. ► Through MD, a typical representation for amorphous BP4 is obtained. ► For the first time we obtain the microscopic atomic picture for the amorphous BP4. ► B retain sp3 electronic bonding while P have coexistence of sp3 and p bonding.