There is an endless quest for new materials to meet the demands of advancing technology. Thus, we need new magnetic and metallic/semiconducting materials for spintronics, new low-loss dielectrics for telecommunication, new multi-ferroic materials that combine both ferroelectricity and ferromagnetism for memory devices, new piezoelectrics that do not contain lead, new lithium containing solids for application as cathode/anode/electrolyte in lithium batteries, hydrogen storage materials for mobile/transport applications and catalyst materials that can convert, for example, methane to higher hydrocarbons, and the list is endless! Fortunately for us, chemistry - inorganic chemistry in particular - plays a crucial role in this quest. Most of the functional materials mentioned above are inorganic non-molecular solids, while much of the conventional inorganic chemistry deals with isolated molecules or molecular solids. Even so, the basic concepts that we learn in inorganic chemistry, for example, acidity/basicity, oxidation/reduction (potentials), crystal field theory, low spin-high spin/inner sphere-outer sphere complexes, role of 𝑑-electrons in transition metal chemistry, electron-transfer reactions, coordination geometries around metal atoms, Jahn-Teller distortion, metal-metal bonds, cation-anion (metal-nonmetal) redox competition in the stabilization of oxidation states - all find crucial application in the design and synthesis of inorganic solids possessing technologically important properties. An attempt has been made here to illustrate the role of inorganic chemistry in this endeavour, drawing examples from the literature as well as from the research work of my group.

Reaction of 1,3-diaryltriazenes (abbreviated in general as HL-R, where R stands for the para-substituent in the aryl fragment and H stands for the dissociable hydrogen atom, R = OCH₃, CH₃, H, Cl, NO₂) with [Rh(PPh₃)₂(CO)Cl] in ethanol in the presence of NEt₃ produces a series of trisdiaryltriazenide complexes of rhodium of type [Rh(L-R)₃], where the triazenes are coordinated to rhodium as monoanionic, bidentate N,N-donors. Structure of the [Rh(L-OCH₃)₃] complex has been determined by X-ray crystallography. The complexes are diamagnetic, and show characteristic ¹H NMR signals and intense MLCT transitions in the visible region. They also fluoresce in the visible region under ambient condition while excited at around 400 nm. Cyclic voltammetry on these complexes shows a Rh(III)-Rh(IV) oxidation (within $0.84-1.67$ V vs SCE), followed by an oxidation of the coordinated triazene ligand (except the R = NO₂ complex). An irreversible reduction of the coordinated triazene is also observed for all the complexes below $-1.03$ V vs SCE.

The reaction of aqueous cobaltous nitrate hexahydrate with the anion of succinimide (sucH) in the presence of excess ethylenediamine (en) in air results in the formation of a dinuclear complex 𝜇-peroxo-bis[bis(ethylenediamine)succinimidato-cobalt(III)] dinitrate dihydrate, 1, in good yield. Compound 1 was characterized by elemental analysis, IR, visible spectra and magnetic susceptibility studies. The explosive nature of [Co(en)₂(suc)(𝜇-O₂)Co(en)₂(suc)](NO₃)₂.2H₂O, 1, precluded its thermal characterization. Compound 1 crystallises in the monoclinic space group $P2_1/c$ and a half of the molecule, constitutes its asymmetric unit. In the centrosymmetric dinuclear complex 1, two Co(III) centres are linked by a planar peroxide bridge. Each cobalt atom is surrounded by four nitrogen atoms of ethylenediamine ligands, a nitrogen atom of succinimidato anion and an oxygen atom of peroxo bridge resulting in a slightly distorted {CoN₅O} octahedron. Due to steric hindrance between the two Co(III) centres, the peroxide bridge is planar with a Co-O-O-Co torsion angle of 180°. The dinuclear complex cation, the nitrate anion and the lattice water are involved in three varieties of H-bonding interactions namely N-H$\cdots$O, O-H$\cdots$O and C-H$\cdots$O.

The kinetics of Ru(III) catalysed oxidation of L-lysine by diperiodatoargentate (III) (DPA) in alkaline medium at 298 K and a constant ionic strength of 0.50 mol dm-3 was studied spectrophotometrically. The oxidation products are aldehyde (5-aminopentanal) and Ag (I). The stoichiometry is i.e. [L-lysine] : [DPA] = 1 : 1. The reaction is of first order in [Ru(III)] and [DPA] and is less than unit order in both [L-lys] and [alkali]. Addition of periodate had a retarding effect on the reaction. The oxidation reaction in alkaline medium has been shown to proceed via a Ru(III)-L-lysine complex, which further reacts with one molecule of monoperiodatoargentate(III) (MPA) in a rate determining step followed by other fast steps to give the products. The main products were identified by spot test, IR, GC-MS studies. The activation parameters with respect to slow step of the mechanism are computed and discussed and thermodynamic quantities are also determined. The active species of catalyst and oxidant have been identified.

Lanthanum-substituted strontium-oxybritholites, Sr$_{10-x}$La$_x$(PO₄)$_{6-x}$(SiO₄)$_{x}$O with $x = 0$, 2 and 4, prepared by solid state reaction were investigated by chemical analysis, powder X-ray diffraction, Raman and ²⁹Si MAS NMR spectroscopies. The refinements of powder XRD patterns of the substituted compounds by the Rietveld method showed that the lanthanum occupied the two metal sites, i.e. (4f) and (6h) sites into the apatite structure, with a clear preference for the (6h) sites. A progressive shift of the free oxygen O(4) towards the centre of the triangles formed by the metal-atoms in the (6h) positions was observed when the lanthanum content increased. It led to the formation of a Sr/La(2)-O(4) strong bond, which might have increased the stability of these compounds. The bands of Raman spectra were assigned to the vibration modes of PO₄ and SiO₄ groups. The comparison of the results of ²⁹Si MAS NMR analysis with those obtained with the ³¹P previously reported, suggested that both species occupied the same crystallographic sites.

In this note we describe the synthesis of cadmium sulphide and selenide nanoparticles from the corresponding novel single source precursors, M[E(Ox)]₂ [E = S (1), Se (2); M = Cd; Ox = 2-(4,4-dimethyl-2-oxazolinyl)benzene] by thermolysing in tri-𝑛-octylphosphine oxide (TOPO) at 280°C, and their characterization by X-ray powder diffraction (XRD), transmission electron microscope (TEM) and scanning electron microscope (SEM) studies.

We report for the first time isolation of Ca@C₉₂ and Ca@C₉₄ by multi-stage highperformance liquid chromatography technique without recycling equipment. It is notable that higher metallofullerenes containing alkaline earth metal ions could be isolated although their relative yields are extremely low. Ca@C₉₂ and Ca@C₉₄ are also confirmed by LD-TOF mass spectrometry and characterrized by UV-Vis-NIR absorption measurements.

Novel tricyclic thienopyrimidines (3, 5, 6, 9, 11, 12) and triazole fused tetracyclic thienopyrimidines (4a-c, 10a-c) were synthesized from precursors 2-amino-6-methyl-4,5,6,7-tetrahydro-1-benzothiophene-3-carbonitrile 1 and 2-amino-7-oxo-4,5,6,7-tetrahydro-1-benzothio-phene-3-carbonitrile 7 respectively. The corresponding precursors were prepared by employing the Gewald reaction. The structures of newly synthesized compounds were characterized by spectral and analytical data. All the compounds were screened for their biological activities. Some of the compounds displayed promising antibacterial and antifungal activities.

Picosecond time-resolved fluorescence measurements have been carried out on 9,9'-bianthryl in three imidazolium ionic liquids to probe the excited state dynamics. In the early time-scale, the fluorescence spectra of bianthryl have been found to consist of emission from both locally excited (LE) and charge transfer (CT) states. The LE → CT relaxation time, as estimated from the decay of the fluorescence intensity of the LE emission, is found to vary between 230 and 390 ps, while the average solvent relaxation time, as estimated from the analysis of time-dependent fluorescence Stokes shift, is found to vary between 620 ps and 1840 ps, depending on the viscosity of the ionic liquids. The results confirm that while in conventional less viscous solvents the CT formation kinetics of bianthryl occurs simultaneously with the solvation dynamics, in ionic liquids the two processes mostly occur in different time scales.

Mesoporous titania was synthesized by a sol-gel method using the surfactants Span85 and X114 as the template. The pore structure was determined by the N₂ adsorption/desorption method below 73 K and calculated using the BJH model. TEM characterizations show that the pores are formed through particle accumulation. Two kinds of channels, straight channels made of cylindrical capillaries and curved channels made of slit-shaped pores, exist in the bulk materials. The influence of the pore structure of mesoporous TiO₂ on its photocatalytic performance was studied. The sample with higher porosity, better textural properties and straight channels are good for photocatalytic performance.

Versatile methods were employed to investigate the chemical reactivity of hydrogenterminated surface of silicon nanowires. The experimental results showed that coupling reaction took place when silicon nanowires reacted with 2,2,2-trifluoroethyl acrylate, and reductive deposition reaction occurred in the presence of inorganic salt such as HgCl₂, and also co-reduction reaction took place in a solution containing both AuCl₃ and PdCl₂. The possible reaction mechanisms were studied and this study would be expected to favour the homogeneity, selectivity, reproducibility, and stability of SiNW devices or sensors.

Temperature dependence on the electro-oxidation of methanol, ethanol and 1-propanol in 0.5 M H₂SO₄ were investigated with Pt and PtRu electrodes. Tafel slope and apparent activation energy were evaluated from the cyclic voltammetric data in the low potential region ($0.3-0.5$ V vs SHE). The CV results provided Tafel slopes for alcohols in the range of 200-400 mV dec^-1 which indicated a difference in the rate determining step. The decrease in Tafel slope was only observed in the case of methanol for the Ru-modified Pt electrode. This indicates that Ru improves the rate of determining step for methanol while hindering it for the other alcohols. The electrochemical impedance spectroscopy was also used to evaluate the electro-oxidation mechanism of alcohols on these electrodes. The simulated EIS results provided two important parameters: charge transfer resistance ($R_{ct}$) and inductance (𝐿). The $R^{-1}_{ct}$ and $L^{-1}$ represent the rate of alcohol electro-oxidation and rate of desorption of intermediate species, respectively. These values increased with the increasing of temperature. The results from two techniques were well agreed that the electro-oxidation of methanol was improved by raising the temperature and ruthenium modification.

Electrochemical cell performances of fluorinated natural graphite (abbreviated as FNG) electrode material was studied by using 1M of LiClO$_{4-}$ EC : DEC : PC (1 : 1 : 1 v%) electrolyte solution with and without 0.15% v/v fluorinated carboxylic ester additive difluoromethyl acetate-CHF₂COOCH₃ (MFA) at -10°C. The electrochemical cell performances were studied by cyclic voltammetry, galvanostatic charge-discharge and impedance analysis. The additive has proven its positive role with the electrolyte system and has shown the improved characterization over the blank electrolyte system.

The electrochemical behaviour of a series of Schiff base i.e. 3-[5-phenylpyrazol-3-ylimino]indol-2-ones (IIa-e) synthesized by the reaction of various 5-substituted isatins with 3-amino-5-phenyl-pyrazole has been investigated and compared with corresponding isatin in dimethylformamide in 0.1 M LiCl using cyclic voltammetry at Hanging Mercury Drop Electrode. All synthesized Schiff bases exhibit a single irreversible two-electron reduction wave in contrast with the two discrete one-electron transfer reduction waves observed for isatin in this medium. Observation of a well-developed single reduction wave can be attributed to the higher basicity of the nitrogen species of the imine bond of Schiff bases, making proton abstraction as well as second electron transfer both rapid. The compounds are subjected to constant potential preparative electrolysis. The products are identified as secondary amines by spectroscopic methods. A mechanism for the electro-reduction process has been proposed. Kinetic parameters have also been calculated.

Studies on surface reactivity of substrate iron (Fe-particles) were made in the tribo-chemical environment of alkyl octadecenoates. Two alkyl octadecenoates namely ethyl octadecenoate and methyl 12-hydroxy octadecenoate, slightly different in their chemical nature, were taken for preparing the chemisorbed reaction films (CRF) at the temperature $100 \pm 5^\circ$C. The reaction products collected in the composite (amorphous) phase were isolated into three different solvent-soluble fractions (sub-layer films) using polar solvents of increasing polar strength. The FTIR analysis of these films showed that these were primarily organic in nature and were composed of alkyl and/or aryl hydroxy ethers, unsaturated hydroxy ketones, and aromatic structures chemically linked with iron surface. These reaction films also contained large amount of iron (Fe). Further, these film fractions also showed varying thermal behaviour during thermal decomposition in the temperature range of $50-800^\circ$C when thermally evaluated in the nitrogen environment.

The Kirkwood-Buff (K-B) integrals play an important role in characterizing the intermolecular interactions in liquid mixtures. These are represented by the K-B parameters, $G_{\text{AA}}$, $G_{\text{BB}}$, and $G_{\text{AB}}$, which reflect correlation between like-like and like-unlike species in the mixture. The K-B integrals of binary mixtures of acetonitrile (ACN) with formamide (FA), N,N-dimethylformamide (DMF), N-methylacetamide (NMA) and N,N-dimethylacetamide (DMA) at 298.15 K and at atmospheric pressure have been computed from the experimental data of ultrasonic speed and density. We have used the similar inverse procedure (as proposed by Ben-Naim) to compute the K-B Parameters of the mixtures, in which thermodynamic information on mixtures such as partial molar volumes, isothermal compressibility, and experimental data of partial vapour pressures are used. A new route has been incorporated by using regular solution theory in the computation of excess free energy for obtaining the partial vapour pressures of binary liquid mixtures. The low values of excess entropy ($S^E \approx 0$) obtained for these mixtures indicate the applicability of regular solution theory to these mixtures. The results obtained regarding intermolecular interaction in all the four mixtures under study from this new procedure are in good agreement with those obtained from the trends exhibited by the excess functions of these mixtures.