Research data supporting 'High stability and luminescence efficiency in donor-acceptor neutral radicals not following the Aufbau principle'

1. Cyclic Voltammetry: .csv files containing CV characteristics of PTM-3NCz, PTM-PDCz, TTM-3NCz, TTM-PPTA, against reference materials: PTM-3NCz, PTM-PDCz, TTM-3NCz, TTM-PPTA, PTM, TTM, NCz, PPTA. The CV measurements were performed with an electrochemical analyser (CHI660E, CH Instruments) using a glass carbon disc as the working electrode. The counter-electrode was a platinum wire. Ag/Ag+ acted as the reference electrode. The redox couple ferrocenium/ferrocene was used as the internal standard; scan rate = 100 mV s−1. Tetrabutylammonium hexafluorophosphate in anhydrous dimethyl formamide and anhydrous dichloromethane (0.1 M) were used as the supporting electrolyte for negative and positive scans, respectively. Current-voltage data are given with applied voltage versus Ag/Ag+ couple. 2. Ultraviolet Photoelectron Spectroscopy: .csv files containing UPS characteristics of PTM-3NCz, PTM-PDCz, TTM-3NCz, TTM-PPTA, against reference materials: PTM-3NCz, PTM-PDCz, TTM-3NCz, TTM-PPTA, PTM, TTM. Thin films (20 nm) were fabricated via spin coating onto clean indium tin oxide (ITO)-coated glass substrates. The UPS spectra were measured at ultrahigh vacuum (10−8 Pa) on a VG Scienta UPS system using monochromatized He Iα irradiation from a discharge lamp (21.22 eV). 3. Absorption and Photoluminescence: .csv files containing wavelength (nm) versus steady-state ultraviolet-visible (UV-VIS) absorption and photoluminescence data are given for PTM-3NCz and PTM. For the UV-VIS absorption and photoluminescence measurements, the materials were dissolved in cyclohexane at a concentration of 1 × 10−5 mol−1. The UV-VIS absorption spectra were measured on a Shimadzu UV-Vis spectrophotometer (UV-2550). The photoluminescence spectra were obtained on a Shimadzu spectrofluorophotometer (RF-5301PC) with 380 nm photoexcitation. 4. Photostability: .csv files containing emission intensity versus time of PTM and PTM-3NCz radicals in dilute cyclohexane. Radicals were dissolved in cyclohexane at a concentration of 5 × 10−5 mol−1. Harmonic of Nd:YAG (yttrium aluminium garnet) laser at 355 nm (pulse width 10 ns, frequency 10 Hz) and power intensity of 21.4 kW cm−2 was used to irradiate the samples. 5. OLED: .csv files containing organic light-emitting diode (OLED) characteristics for PTM-3NCz device. The device was fabricated as described in the main text by solution processing and vacuum deposition of charge transport and host-guest layers, and a metal electrode. The current–voltage–radiance characteristics were measured using a Keithley 2400 source meter, a Keithley 2000 multimeter and a calibrated Si photodiode, which was placed at a fixed distance from the devices. External quantum efficiencies were calculated from on-axis irradiance with assumption of Lambertian emission profile and consideration of photodiode quantum efficiency across the electroluminescence spectrum. The electroluminescence profile was obtained with a fibre spectrometer (Flame-S-VIS-NIR-ES, Ocean Optics). All the measurements were carried out at room temperature under ambient conditions.