Organic semiconducting materials have attracted interest for a number of advantages they offer over traditional inorganic counterparts. In particular, tetracene (Tc) has been noted for its low cost, tunability through functionalization, and ability to undergo singlet fission—a process which has demonstrated the potential to increase solar cell efficiency. One characteristic feature of Tc is its tendency to form crystalline structures conducive to intermolecular interactions. Additionally, the reactivity of Tcand its derivatives largely inhibit their capability for use in devices. In order to resolve this, it is important to study Tc degradation products. In the first half of this work, thechemical structure of an alkyne photodimer previously detected in anaerobic TIPS-Tcsamples exposed to 532 nm irradiation is revisited and compared with an alternative structure. In the latter half, select dimer pair configurations observed in the crystalline packing structures of five functionalized Tc derivatives are considered and electronic excited state couplings are estimated.