An imidazolyl-pyreno-imidazole conjugate as a cyanide sensor and a set–reset memorized sequential logic device

Abstract

In this work a pyrenyl-bisimidazole receptor has been synthesized and fully characterized by standard analytical tools and spectroscopic techniques including single crystal X-ray crystallography. Crystal structure analysis shows the occurrence of strong π-π and CH-π interactions among the adjacent Py-BiimzH2 units. Moreover, each NH proton on the imidazole ring is involved in strong intermolecular hydrogen bonding interactions with N atoms of the neighboring unit forming infinite chains. The absorption and both steady state and time-resolved emission properties of the compound were found to be modulated to a significant extent by selective inorganic anions and transition metal cations in solution. Theoretical calculations employing density functional theory (DFT) and time-dependent density functional theory (TD-DFT) were carried out and good correlation between the experimental and the TD-DFT calculated results led to the accurate assignment of the main absorption and emission bands of the original compound as well as its anionic and metal complexes. More importantly, the compound can act as an efficient ratiometric optical chemosensor for CN(-) in H2O-DMSO (9 : 1) media. The anion sensing properties of the receptor was thoroughly investigated in both neat DMSO as well as mixed H2O-DMSO (9 : 1) media through different channels. From the response profiles in terms of absorption or emission intensity and wavelength towards inorganic ions (Cu(2+) and CN(-)), we developed a molecular system which can mimic sequential Boolean logic functions of XOR, OR, XNOR and NOR logic gates. Moreover, we were able to construct a memory device which nicely demonstrates the "Write-Read-Erase-Read" behavior.

A ratiometric chemosensor for Al3+ based on naphthalene-quinoline conjugate with the resultant complex as secondary sensor for F−: Interpretation of molecular logic gates

“…Various types of simple and complicated logic gates have been mimicked by different molecular systems based on their responses in spectroscopic techniques with external stimuli e.g. chemicals as inputs leading to a readable output [46][47][48][49][50][51][52][53][54][55][56].…”

Polypyridyl-imidazole based smart Ru(II) complex mimicking advanced Boolean and Fuzzy logic functions

“…(1) IF n F À /n 1 AND n Zn 2þ /n 1 are null, THEN quantum yield (U F ) is medium (2) IF n F À /n 1 is low AND n Zn 2þ /n 1 is low, THEN quantum yield (U F ) is medium (3) IF n F À /n 1 is low AND n Zn 2þ /n 1 is medium, THEN quantum yield (U F ) is medium (4) IF n F À /n 1 is low AND n Zn 2þ /n 1 is high, THEN quantum yield (U F ) is high (5) IF n F À /n 1 is medium AND n Zn 2þ /n 1 is low, THEN quantum yield (U F ) is medium (6) IF n F À /n 1 is medium AND n Zn 2þ /n 1 is medium, THEN quantum yield (U F ) is medium (7) IF n F À /n 1 is medium AND n Zn 2þ /n 1 is high, THEN quantum yield (U F ) is high (8) IF n F À /n 1 is high AND n Zn 2þ /n 1 is low, THEN quantum yield (U F ) is low (9) IF n F À /n 1 is high AND n Zn 2þ /n 1 is medium, THEN quantum yield (U F ) medium (10) IF n F À /n 1 is high AND n Zn 2þ /n 1 is high, THEN quantum yield (U F ) is high Fig. 13.…”

“…IF n Fe 2þ /n 1 is low AND n F À /n 1 is high, e is low is low (6) IF n Fe 2þ /n 1 is medium AND n F À /n 1 is low, THEN e is medium (7) IF n Fe 2þ /n 1 is medium AND n F À /n 1 is medium, THEN e is medium (8) IF n Fe 2þ /n 1 is medium AND n F À /n 1 is high, THEN e is low (9) IF n Fe 2þ /n 1 is high AND n F À /n 1 is low, THEN e is high (10) IF n Fe 2þ /n 1 is high AND n F À /n 1 is medium, THEN e is medium (11) IF n Fe 2þ /n 1 is high AND n F À /n 1 is high, THEN e is low induced by combinations of multiple inputs are of great recent interest. To this end, we monitored the emission intensity at 622 nm as the output signal in presence of four ionic inputs (Fe 2+ as input 1, Ni 2+ as input 2, Cu 2+ as input 3 and H + as input 4).…”

Multifunctional Logic Applications of a Single Molecule: A Molecular Photo‐Switch Performing as Simple and Complex Gates, Memory Element, and a Molecular Keypad Lock

“…Now, for the purpose of manufacturing memory devices that are capable of storing information and information processing at the molecular level, the reversible and reproducible fluorescence switching process of CZ could be employed to design a useful sequential logic circuit displaying “Erase‐Read‐Write‐Read” behaviour in the form of binary logic. Memory devices operate through feedback loop where one of the outputs serves as input and is memorized as a “memory element” ,. Thus, based on the above principle we were able to design a sequential logic circuit displaying “Erase‐Read‐Write‐Read” with the help of binary logic employing on CZ as device (Figure ).…”