Naphthalene-1,8-dicarb-oxy-lic anhydride: a monoclinic polymorph

Area of Science:

• Crystallography
• Materials Science
• Organic Chemistry

Background:

• Naphthalene-1,8-dicarboxylic anhydride exists in multiple polymorphic forms.
• Previous polymorphs were reported in orthorhombic space groups P2(1)2(1)2(1) and Pbca.

Purpose of the Study:

• To synthesize and characterize a new polymorphic form of naphthalene-1,8-dicarboxylic anhydride.
• To determine the crystal structure of the newly synthesized polymorph.

Main Methods:

• Hydrothermal synthesis.
• Single-crystal X-ray diffraction.

Main Results:

• A new polymorph of naphthalene-1,8-dicarboxylic anhydride was successfully synthesized.
• The crystal structure was determined to be in the monoclinic space group P2(1)/c.
• The planar molecules exhibit a total puckering amplitude Q = 0.0362(15) and are arranged parallel along the a axis.

Conclusions:

• A novel monoclinic polymorph of naphthalene-1,8-dicarboxylic anhydride has been identified.
• This discovery expands the known polymorphic landscape of this compound.
• The structural characterization provides insights into molecular packing in crystalline organic anhydrides.