Ashoka University is a private university located in Sonipat, Haryana, India, focusing on liberal arts and sciences. It was established in 2014.&nbsp;It is guided by an academic council of academics and scholars from around the world. The council sets the university&#39;s academic standard, advising on matters of curriculum, faculty hiring and research.&nbsp;

Ashoka University offers a full-time 3 (+ 1) year undergraduate programme. The University comprises of&nbsp;2500 plus students, with a mix of both national and international students.&nbsp; &nbsp;

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Ashoka University

Organic molecules with an active dipole moment have a natural propensity to align in an antiparallel fashion in the solid state, resulting in zero macroscopic polarization. This primary limitation makes the material unresponsive to switching with electric fields, mechanical forces, and to intense laser light. A single-component organic material that bestows macroscopic dipole-driven electro-mechanical and optical functions, e.g., piezoelectric, ferroelectric and nonlinear optical (NLO) activity, is unprecedented due to the design challenges imparted by crystal symmetry and dipole orientations. Herein we report a crystalline organic material that self-assembles with a polar order (P1), and is endowed with a high piezoelectric coefficient (d33-47 pm V−1), as well as ferroelectric and Debye-type relaxor properties. In addition, it shows second harmonic generation (SHG) activity, which is more than five times that of the benchmark potassium dihydrogen phosphate. Piezoelectric force microscopy (PFM) images validated electro-mechanical deformations. Piezoresponse force spectroscopy (PFS) studies confirmed a signature butterfly-like amplitude and a phase loop. To the best of our knowledge, this is the first report of a folded supramolecular π-system that manifests unidirectionally oriented dipoles and exhibits piezoelectricity, ferroelectricity, and has excellent ability to generate second harmonic light. These findings can herald new design possibilities based on folded architectures to explore opto-, electro- and mechano-responsive multifaceted functions. © 2023 The Royal Society of Chemistry.

World University root node

Department of Chemistry

Chemical Science

A folded p-system with supramolecularly oriented dipoles: single-component piezoelectric relaxor with NLO activity

Dipolar coupled multi-spin systems have the potential to be used as molecular qubits. Herein we report the synthesis of a molecular multi-qubit model system with three individually addressable, weakly interacting, spin urn:x-wiley:14337851:media:anie202207947:anie202207947-math-0001 centres of differing g-values. We use pulsed Electron Paramagnetic Resonance (EPR) techniques to characterise and separately address the individual electron spin qubits; CuII, Cr7Ni ring and a nitroxide, to determine the strength of the inter-qubit dipolar interaction. Orientation selective Relaxation-Induced Dipolar Modulation Enhancement (os-RIDME) detecting across the CuII spectrum revealed a strongly correlated CuII-Cr7Ni ring relationship; detecting on the nitroxide resonance measured both the nitroxide and CuII or nitroxide and Cr7Ni ring correlations, with switchability of the interaction based on differing relaxation dynamics, indicating a handle for implementing EPR-based quantum information processing (QIP) algorithms.

Angewandte Chemie - International Edition

Modelling Conformational Flexibility in a Spectrally Addressable Molecular Multi-Qubit Model System

Ferrocene since its inception in the year 1951, has been extensively exploited as a crucial redox probe to unravel electrochemical charge-transfer dynamics in a variety of platforms ranging from solution-based systems and molecular thin-films to solid-state molecular electronics and spintronic devices. Having completed almost 71&nbsp;years of its existence, ferrocene has now become one of the most widely studied organometallic compounds. Several experimental and theoretical frameworks are made to understand ferrocene's electronic and electrochemical properties. Ferrocene is an 18-electron metallocene that shows interesting metal–ligand coordination and has led to the preparation of a great number of important molecules. Ferrocene and its numerous derivatives have brought a breakthrough in metallocene chemistry. Ferrocene represents a chemically and thermally stable system that undergoes reversible electrochemical oxidation and reduction processes. Ferrocene-based self-assembled monolayers (SAMs) are considered as model system for performing on-surface redox reactions and have been applied to create nanoelectronic devices for molecular switching, rectification, and low-voltage operational memory devices. The present review discusses the recent progress made toward a ferrocene-containing molecular system that have been utilized in redox reactions, surface attachment, spin-dependent electrochemical processes to understand spin polarization, photo-electrochemistry, and molecular electronic devices. This review provides an excellent platform for understanding the electrochemical properties and the rational design of ferrocene-based molecular systems for optoelectronic applications.

COORDINATION CHEMISTRY REVIEWS

Ferrocene as an iconic redox marker: From solution chemistry to molecular electronic devices

Polymer beads have been used as the core of magnetic particles for around twenty years. Here we report studies to attach polymetallic complexes to polymer beads for the first time, producing beads of around 115 microns diameter that are attached to 1014 hybrid inorganic-organic [2]rotaxanes. The bead is then formally a [1014] rotaxane. The number of complexes attached is counted by EPR spectroscopy after including TEMPO radicals within the thread of the hybrid [2]rotaxanes.

Fulltext

Communications Chemistry

Decorating polymer beads with 1014 inorganic-organic [2]rotaxanes as shown by spin counting

Nanomaterials that can perform cascading functions in the domain of rapidity and strength of self-assembly, able to immobilize a large mass with minimum energy, and generate optical signal hold potential to contain recurring oil-spills and remediation of land or water bodies. Herein, we report the stimuli-free, phase-selective immobilization of naturally occurring heavy crude oil. Molecule(s) described herein are capable of forming nanofibers with large-area junction zones and instantaneously immobilize petroleum products (PPs), and also report the event with a turn-on emission. The extraordinary efficiency of 0.4 kg immobilizer per ton of petrol and wide operational temperature range (up to 330–360 K) stems from the rapid creation of advanced assemblies having strength (&gt;105 Pa) akin to the robust polymeric fibers. Thus, this new generation of intelligent nanomaterials with ingrained information to carry out multiple and complex function in tandem offers bright prospects to control and effectively detect the oil spill menace in a proficient manner.

ChemNanoMat

Acridine-Peptide Conjugated Nanofiber Assembly Triggers Stimuli-Free Immobilization of Crude Oil and Read-Out by Turn-On Emission

Chirality, ubiquitous in biological systems, is the property of the non-superimposable structures found in both macroscopic and nanoscopic objects. In the last ten years, the research on chiral inorganic nanomaterials has witnessed tremendous growth due to their shape, size, crystal facets-controlled unparalleled physical, chemical, optoelectronic, and bio-compatibility features. Due to the quantum confinement, the chiral nanomaterials exhibit high anisotropy factors and, therefore, there has been an upsurge in research activities around the chiroptical and (bio)recognition properties of optically active inorganic nanomaterials. Advancements in synthesis and characterization technologies have made it possible to prepare complex multi-functional materials. Inorganic nanoparticles are known to exhibit fascinating semiconducting or metallic behavior and when combined with chirality, their usability in various devices is enhanced drastically due to an additional degree of freedom over achiral systems. In this review, we discuss different chemical routes to transfer chirality from intrinsic chiral systems into achiral nanomaterials for optoelectronics and bio-applications, in the light of recent experimental findings. Despite the progress in the research field of nanomaterials, imprinting chirality, device fabrication, scalability, long-term stability, and reproducibility remain challenging tasks that need to be addressed. Since the synthesis and growth mechanisms of chiral inorganic systems can be found in literature, here, we shed light only on the complimentary metal-oxides semiconductors (CMOS), and bio-compatibility of either intrinsic or imprinted chiral nanomaterials and their potential applications in next-generation chiroptical devices. We also discuss feasible strategies to resolve existing issues related to the integration into devices and their operational aspects.&nbsp;