On observing C₆₀⁺ and C₆₀²⁺ in laboratory and space

Karlsruhe Institute of Technology, Institute of Physical Chemistry II, 76131 Karlsruhe, Germany
e-mail: dmitry.strelnikov@kit.edu

Received: 24 August 2015
Accepted: 18 October 2015

Abstract

Recently, we have measured the IR absorptions of C₆₀⁺, C₆₀⁻, and C₆₀²⁺ in neon matrixes. Many previously unknown absorptions were established. Here we compare our laboratory IR absorption spectra for C₆₀⁺ and C₆₀²⁺ to the IR emission spectra of several astronomical objects that show C₆₀ emission. We find that IR bands of C₆₀⁺ are possibly present in the objects Tc1, SMP SMC 16, NGC 7023, NGC 2244, and SMP LMC 02. Infrared emission features possibly due to C₆₀²⁺ were identified in NGC 7023. To help with future observations of fullerene-related DIBs, we also revisited the oscillator strengths of the NIR absorptions of C₆₀⁺, and report significantly revised values. Additionally, we report the UV oscillator strengths of C₆₀⁺.