Perylenetetracarboxylic dianhydride

Perylenetetracarboxylic dianhydride

Names
Other names Perylene-3,4,9,10-tetracarboxylic dianhydride, Pigment Red 224
Identifiers
CAS Number	128-69-8
ECHA InfoCard	100.004.461
CompTox Dashboard (EPA)	DTXSID1059577
Properties
Chemical formula	C24H8O6
Molar mass	392.32
Density	1.7 g/cm3
Melting point	~350 °C
Structure
Crystal structure	Monoclinic, P21/c
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Perylenetetracarboxylic dianhydride (PTCDA) is an organic compound used commercially as a precursor to pigments and dyes. It is generated by oxidative fusion of naphthalene dicarboxylic anhydride via naphthalimide. PTCDA reacts with amines to give a range of useful colorants.

Structure

Atomic force microscopy image of a single PTCDA molecule on Si at room temperature.

Self-assembly of PTCDA molecules on NaCl, scanning tunneling microscopy image.

PTCDA occurs in two crystalline forms, α and β. Both have the P2₁/c monoclinic symmetry and a relatively high for organic compounds density of ca. 1.7 g/cm³. Their lattice parameters are: a = 0.374 nm, b = 1.196 nm, c = 1.734 nm, γ = 98.8° for α and a = 0.378 nm, b = 1.930 nm, c = 1.077 nm, γ = 83.6° for β phase.