  Interstellar infrared observation shows featured spectrum due to polycyclic
aromatic hydrocarbon (PAH)at wavelength 3.3,6.2,7.6,7.8,8.6,and 11.3
micrometer,which are ubiquitously observed in many astronomical dust clouds and
galaxies. Our previous first principles calculation revieled that viod induced
coronene (C23H12)2+ and circumcoronene (C53H18)1+ could reproduce such spectrum
very well. In this study, quantum-mechanic origin was studied through atomic
configuration change and atomic vibration mode analysis. By a high speed
particle attack, carbon void would be introduced in PAH. Molecular
configuration was deformed by the Jahn-Teller quantum effect. Carbon SP3 local
bond was created among SP2 graphene like carbon network. Also, carbon
tetrahedron local structure was created. Such peculiar structure is the quantum
origin. Those metamorphosed molecules would be photo-ionized by the central
star strong photon irradiation resulting cation molecules. Atomic vibration
mode of cation molecule (C23H12)2+ was compared with that of neutral one
(C23H12). At 3.3 micrometer, both molecules show show C-H stretching mode and
give fairly large infrared intensity. At 6.2,7.6,7.8, and 8.6 micrometer bands,
cation molecule show complex C-C stretching and shrinking mixing modes and
remain large infrared emission. Whereas, neutral molecule gives harmonic
motion, which cancelles each other resulting very small infrared intensity. At
11.3 micrometer, both neutral and cation molecules show C-H bending motion
perpendicular to a molecular plane, which contributes to strong emission.
Actual observed spectrum would be a sum of such quantum-mechanic origined
molecules.
