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The Alborz Mountains in north Iran underwent several tectono-metamorphic events during opening and closure of the Palaeotethys and Neotethys Oceans. These events are recorded by rare and discontinuously exposed metamorphic rocks, such as the HP-LT Asalem-Shanderman Complex and the Gasht Metamorphic Complex (GMC), that are considered to have been metamorphosed during the closure of the Palaeotethys Ocean. The GMC comprises poorly exposed metasediments and amphibolites metamorphosed under greenschist- to amphibolite-facies conditions, along with smaller volumes of granites. Different dating methods were applied to selected samples of the GMC basement to constrain the geological evolution of this part of the Alborz Mountains. A metagranite yielded two LA-ICP-MS U–Pb zircon ages of 638.4 ± 4.1 Ma and 590.3 ± 4.8 Ma that possibly date protolith crystallisation and later deformation and metamorphism, respectively, and a granite yielded a late Ediacaran 551 ± 2.5 Ma U–Pb zircon crystallisation age. A northern provenance from the basement to the South Caspian Basin can neither be established nor ruled out because no age data are available for this unit. Derivation of the GMC from Turan Block basement is unlikely, as this has a different crustal makeup and is probably composed of Paleoproterozoic and early Neoproterozoic material. The zircon ages are similar to published ages from the Arabian-Nubian Shield, indicating that this part of the Alborz basement may have belonged to the northern margin of Gondwana in the Neoproterozoic before rifting and drifting away along with other Iranian blocks (the Cimmerian terranes) during opening of the Neotethys Ocean. Chemical Th-U-total Pb ages for metamorphic monazites from two metapelite samples yielded a very large range of spot ages, of which c. 80% falls between 200 and 250 Ma, that do not allow to distinguish between Eo-Cimmerian and Main Cimmerian events in the GMC. However, they may indicate that the amphibolite-facies peak metamorphism of the GMC occurred sometime in the Triassic, in any case much later than the Carboniferous metamorphism in the neighbouring Asalem-Shanderman Metamorphic Complex to the north. Peak-metamorphic amphibole from amphibolite, retrograde white mica and foliation-defining biotite from metapelites and magmatic white mica from granite yielded much younger 175.1 ± 0.5 to 177.0 ± 0.4 Ma 40Ar/39Ar plateau ages. The Toarcian 40Ar/39Ar ages for minerals with different nominal closure temperatures reflect very rapid cooling of GMC basement below the Shemshak Group due to extension-triggered uplift. This late Toarcian to Aalenian extension event can be correlated with the regional Mid-Cimmerian unconformity of mid-Bajocian age (c. 170 Ma) that resulted from the tectonic movements causing rapid uplift and erosion. Extension probably started in the western Alborz Mountains in the Toarcian, migrated eastward, and culminated in the Aalenian in the eastern Alborz with the formation of a deep-marine basin. It was probably triggered by the onset of the subduction of Neotethys oceanic crust beneath the Central Iranian Microcontinent. [ABSTRACT FROM AUTHOR]

In this study, a low‐melting organic‐inorganic crystalline ionic liquid compound, N‐butyl pyridinium tetrachlorido ferrate (III) is described. The material can easily be synthesized using a one‐pot approach in an ionic liquid medium. Single‐crystal X‐ray diffraction confirms that the basic inorganic block is [FeCl4]−, which is counterbalanced by an N‐butyl pyridinium cation. The compound exhibits a melting point of 37.6 °C by differential scanning calorimetry, which is among the lowest values for a pyridinium‐based metal‐containing ionic liquid. The material shows promising electrochemical behavior at room temperature in both aqueous and nonaqueous solvents, and at elevated temperatures in its pure liquid state. Given its appreciable solubility in both water and acetonitrile, the compound can act as a redox‐active species in a supporting electrolyte for redox flow battery applications. These classes of low‐melting ionic solids with long‐range order and interesting electrochemical applications are potential candidates for a range of green energy storage and harvesting systems. [ABSTRACT FROM AUTHOR]

Hexagonal p-type semiconductor CuS nanoplates were synthesized via a hot injection method from bis(trimethylsilyl)sulfide and the ionic liquid precursor bis(N-dodecylpyridinium) tetrachloridocuprate(ii). The particles have a broad size distribution with diameters between 30 and 680 nm and well-developed crystal habits. The nanoplates were successfully incorporated into organic photovoltaic (OPV) cells as hole conduction materials. The power conversion efficiency of OPV cells fabricated with the nanoplates is 16% higher than that of a control device fabricated without the nanoplates. [ABSTRACT FROM AUTHOR]