What will be the dihedral angle present in hydrogen peroxide (H2O2) in solid phase.
The dihedral angle is the angle between two planes defined by the atoms in a molecule. For hydrogen peroxide (H₂O₂), which has a structure of H-O-O-H, the dihedral angle is the angle between the two H-O-O planes. This angle arises due to the torsional rotation around the O-O bond and is influenced by electronic effects and phase (gas, liquid, solid).
In the solid phase, molecules often adopt specific conformations due to crystal packing forces and hydrogen bonding. For H₂O₂, experimental studies (e.g., X-ray crystallography) show that the dihedral angle is approximately:
Step 1: Understand the molecular structure – H₂O₂ has a non-linear, non-planar geometry with a skew conformation.
Step 2: Recall that the dihedral angle varies with phase. In gas phase, it is about 111.5° due to repulsion, but in solid phase, intermolecular forces modify it.
Step 3: In solid H₂O₂, the molecules form hydrogen-bonded networks, which constrain the conformation. Measurements confirm the dihedral angle is close to 90.2°.
Final Answer: The dihedral angle in solid hydrogen peroxide is .
The dihedral angle (φ) is defined for four atoms A-B-C-D as the angle between the plane containing A-B-C and the plane containing B-C-D. It can be calculated using vector math:
For H₂O₂, the observed angle is experimentally determined due to complex electronic and steric factors.