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A novel series of D-bridge-A type organic small molecules has been designed, synthesized, and evaluated for non-volatile resistive switching write-once read-many (WORM) memory application. This study explores structure–property relationships by coupling electron-deficient malononitrile units with donors such as dibenzofuran, dibenzothiophene, and triphenylamine. Photophysical investigations revealed significant intramolecular charge transfer interaction, while electrochemical analyses demonstrated optimal band gaps ranging from 2.20 to 3.10 eV. All synthesized compounds exhibited robust, non-volatile, resistive switching memory capabilities, with ON/OFF ratios spanning 102 to 103. The lowest recorded threshold voltage was −1.25 V, and devices demonstrated substantial stability with retention times of 103 s. Notably, triphenylamine-based compounds displayed superior memory performance compared to their counterparts. The solubility of the compounds in common organic solvents suggests that they are viable for cheap fabrication techniques. Density functional theory calculations were used to visualize the key molecular orbitals and support the proposed mechanisms for resistive switching. The strategic implementation of equipotential donors and acceptors is highly desirable. This well-rounded approach guarantees optimal performance and fosters broader applicability of these devices. [ABSTRACT FROM AUTHOR]

Dead cell sorting is pivotal and plays a very significant role in homeostasis. Apoptosis and ferroptosis are the two major regulatory cell death processes. Apoptosis is a programmed cell death process, while ferroptosis is a regulatory cell death process. Monitoring the dead cells coming out from these processes is extremely important to stop various cellular dysfunctions. Here, we present a single NIR emissive probe that can observe both apoptotic and ferroptosis regulatory cell deaths. We were able to directly visualize the dead cells in both animal and plant cells upon a significant increase in the fluorescence intensity of the probe. During cell death, the increased cytoplasm viscosity restricted the rotor motion and helped in the fluorescence turn-on of the probe. Lysosomal viscosity was found to play a crucial role in the ferroptosis pathway. On the other hand, the probe was not only efficient in mapping the viscosity in various parts of live Caenorhabditis elegans (C. elegans) bodies but also able to differentiate between live and dead animals. [ABSTRACT FROM AUTHOR]

Photoresponsive conjugated polymers are a promising target for modern organic electronics. Numerous photoswitchable repeat units have been included covalently within polymeric structures to enable responsive chromic materials, most commonly through side‐chain appendages or through formal conjugation along a π‐conjugated backbone. We recently disclosed a new design whereby the photoswitch elements are cross conjugated to a conjugated polymer main chain. In this case, we found that the extent of photoconversion was dictated in part by competitive main chain light absorption, which could be suppressed by using a photoswitching motif that carried most of the frontier molecular orbital densities. Here, we report the modeling and synthesis of a series of thieno[3,4‐b]thiophene (TT)‐based photochromes with various aromatic flankers imparting varying degrees of steric bulk and π‐conjugation in order to elucidate the balancing act between steric and electronic factors to promote photochromism. These model systems provide a better understanding of the behavior of photochromic units within extended oligomeric and polymeric π‐conjugated materials. [ABSTRACT FROM AUTHOR]