[meso-Tetrakis(pentafluorophenyl)porphyrinato]platinum(ii) as an efficient, oxidation-resistant red phosphor: spectroscopic properties and applications in organic light-emitting diodesElectronic supplementary information available: details of photoluminescence measurements, transient absorption spectra of PtF20TPP, photophysical properties of PtF20TPP in different solvents, EL spectra and performances of OLEDs using PtF20TPP as emitters at various doping levels and crystallographic data for PtF20TPP. See http://www.rsc.org/suppdata/jm/b2/b212204a/