The incorporation of trityl and triphenylsilyl groups into low molecular weight molecules allows the formation of stable molecular glasses. A series of materials based on the N-phenyldiethanolamine core was synthesized bearing different azobenzenes and benzylydene-1,3-indandione as active chromophores. Molecular hyperpolarizability of the synthesized compounds was calculated by a restricted Hartree–Fock method with basis 6-31G(d,p) and measured in solutions by hyper-Rayleigh scattering. Non-linear optical (NLO) activity of the thin glassy films was confirmed after a corona poling procedure. Thermal sustainability of the NLO response of up to 85 °C was achieved. Quantum chemical calculations of the compounds revealed increased steric bulk and conformational freedom of the triphenylsilyl moiety. While the presence of the triphenylsilyl group results in more stable glasses and increased material nonlinearity, in the case of trityl groups, measured glass transition temperatures are higher.

A series of organic push–pull type chromophores using indane-1,3-dione 5-carboxylic acid (IDCA) and novel 1,3-bis(dicyanomethylidene)indane 5-carboxylic acid (CICA) electron acceptor fragments have been synthesized and characterized. NMR and X-ray analysis revealed that condensation reactions with the CICA fragment were stereoselective and yielded benzylidenes and azomethines with E double bond configurations. Due to the non-planar geometry these compounds are chiral and were acquired as a racemic mixture. The subsequent functionalization of the carboxylic acid group with 5,5,5-triphenylpentan-1-ol yielded solution-processable glass forming materials (6, 8, 10, 13) with glass transition temperature values of 76–134 °C. The nonlinear optical (NLO) properties of these compounds were characterized using quantum chemical calculations and second harmonic generation (SHG) measurements in corona-poled thin glassy films. The twisted geometry of the CICA based materials was shown to be beneficial to the macroscopic NLO performance due to the less pronounced solid phase stacking compared to the flat IDCA based compounds. The presence of site isolating groups at both the acceptor and donor ends of the molecule in compound 13 resulted in a considerable NLO efficiency increase. Non-centrosymmetric crystals of CICA based N,N-dimethylaminobenzylidene 7b were obtained and showed a SHG response comparable to urea.

Reaction of elemental sulfur with 2-R¹ and 2,8-R¹,R²-substituted tetracenes (2) in refluxing DMF affords 5,6,11,12 tetrathiotetracenes (1) in good yields (74–99%) for a range of substituents where R¹,R² are: H,H (a); Me,H (b); MeO,H (c); Ph,H (d); Me,Me (e), iPr,Me (f, iPr = iso-propyl, CHMe₂), Me,MeO (g); MeO,MeO (h). The reaction rate is limited only by the solubility of the tetracene (2); 2g–h being both the least soluble and slowest reacting. At partial conversion recovered single crystalline 2g led to its X-ray structure determination. Vacuum deposited (substrate deposition temperature 300 K, pressure 7 × 10⁻⁶ mbar, source temperature 500 K) thin films from 1 (of initial 88–99% purity) show final electrical conductivities, σ_{(in plane)} from 1.40 × 10⁻⁵ S cm⁻¹ (1g) to 3.74 × 10⁻⁴ S cm⁻¹ (1b) for the resultant near pristine films; while 1d proved too involatile to be effectively sublimed under these conditions. In comparison, initially 95% pure TTT (1a) based films show σ_(in-plane) = 4.33 × 10⁻⁵ S cm⁻¹. The purities of 1a–h are highly upgraded during sublimation. Well defined micro-crystallites showing blade, needle or mossy like habits are observed in the films. The Seebeck coefficients (S_b) of the prepared 1 range from 374 (1c) to 900 (1f) μV K⁻¹ (vs. 855 μV K⁻¹ for identically prepared 95% pure TTT, 1a). Doping of films of 1f (R¹ = iPr, R² = Me) with iodine produces optimal p-type behaviour: σ_(in-plane) = 7.00 × 10⁻² S cm⁻¹, S_b = 175 μV K⁻¹. The latter's power factor (PF) at 0.33 μW m⁻¹ K⁻² is more than 500 times that of the equivalent I₂-doped TTT films (1a, R¹ = R² = H), previously regarded as the optimal material for thin film thermoelectric devices using acene radical cation motifs.