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Electron spin superpositions represent a critical component of emergent quantum technologies in computation, sensing, encryption, and communication. However, spin relaxation (T₁) and decoherence (T_m) represent major obstacles to the implementation of molecular quantum bits (qubits). Synthetic strategies have made substantial progress in enhancing spin coherence times by minimizing contributions from surrounding electron and nuclear spins. For room-temperature operation, however, the lifetime of spin coherence becomes limited by coupling with vibrational modes of the lattice. Using pulse electron paramagnetic resonance (EPR) spectroscopy, we measure the spin-lattice relaxation of a vanadyl tetrapyrazinoporphyrazine complex appended with eight peripheral 2,6-diisopropylphenol groups (VOPyzPz-DIPP) and compare it to the relaxation of the archetypical vanadyl phthalocyanine molecular qubit (VOPc). The added peripheral groups lead to distinctly different spin relaxation behavior. While similar relaxation times are observed at low temperatures and ambient conditions, significant changes are observed for the orientation dependence of T₁at 100 K, as well as the temperature dependence of T₁over the intermediate temperature range spanning [Formula: see text]10–150 K. These results can be tentatively interpreted as arising from loosened spin-phonon coupling selection rules and a greater number of accessible acoustic and optical modes contributing to the spin relaxation behavior of VOPyzPz-DIPP relative to VOPc. 

Metal-free, magnesium, titanyl, and vanadyl tetrapyrazinoporphyrazines substituted with eight 2,6-diisopropylphenoxy groups at the peripheral positions were prepared and characterized by NMR, UV-Vis, magnetic circular dichroism (MCD), and mass spectrometry methods. In addition, the Pc^(2,6iPrPhO)8VO complex was characterized by EPR spectroscopy and X-ray crystallography. Reaction between TiCl₄with 4,5-(2,6-diisopropylphenoxy)phthalonitrile in N,N-dimethylaminoethanol resulted in the formation of a red open-chain trimer, which was characterized by mass spectrometry and X-ray crystallography. Electronic structures of new compounds and their excited state properties were probed by Density Functional Theory (DFT) and Time-Dependent DFT (TDDFT) methods. 

Abstract This article explores the foundations of religious influence in politics and society. We show that an important Islamic institution fostered the entrenchment of Islamism at a critical juncture in Indonesia, the world’s largest Muslim country. In the early 1960s, rural elites transferred large amounts of land into waqf—inalienable charitable trusts in Islamic law—to avoid expropriation by the state. Regions facing a greater threat of expropriation exhibit more prevalent waqf land and Islamic institutions endowed as such, including mosques and religious schools. These endowments provided conservative forces with the capital needed to promote Islamist ideology and mobilize against the secular state. We identify lasting effects of the transfers on the size of the religious sector, electoral support for Islamist parties, and the adoption of local sharia laws. These effects are shaped by greater demand for religion in government but not by greater piety among the electorate. Waqf assets also impose costs on the local economy, particularly in agriculture, where these endowments are associated with lower productivity. Overall, our findings shed new light on the origins and consequences of Islamism.