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A new approach for the development of nano-sized spectroscopic-based early-warning sensors using molecular electrostatic potentials (MEP) and molecular vibronics (MV) was presented. The use of MEPs allow us to sense and detect specific molecules in elaborated arrays of logical gates which provide the signature of the trapped species and a decision signal of the results of the sensing operation. Molecular vibronics is used to activate/deactivate, control and program the detection process as well as to transmit the information to and from nano-micro interfaces that allow the interaction with microelectronic systems. In order to develop this scenario, it is needed to explain the exact reasons, from an atomistic point of view rather than using phenomenological models the effects of molecules on nanoclusters. We present here a study of silicon-phenyl complexes.

The co-adsorption of carbon monoxide and benzene on Co(0001) has been studied using density functional calculations. We used the ordered surface unit cell. A comparison of the co-adsorption with CO and benzene two-dimensional networks is also given. The electronic structure reveals that the CO orbitals interact with benzene and Co layer. Regarding the bonding, the Co–Co overlap population decrease 18% after benzene adsorption and increase a little after CO adsorption with a net 14.6% decrease in the co-adsorption system. The CO–benzene interaction is shown by the changes in the C–O (CO) and C–H (benzene) bonds.

The adsorption of small organic molecules on silicon surfaces has been long a subject of investigations, as it provides the fundamental basis of silicon-based technologies in many fields. Several approaches were used, both theoretical and experimental, on many types of adsorbate-substrate systems aiming at determining preferential sites and geometries of adsorption, stable configurations, transition barriers, adsorption mechanisms, electronic structures among others. The research efforts, though, did not always bring to conclusive arguments and on some systems investigations are still going on following the evolution of the experimental techniques and computational methods. In this review, two case studies are reported: benzene and methanol on Si(100)2$\times$1, i.e. examples of a molecular and a dissociative adsorption. The adsorption of benzene on Si(100)2$\times$1 is still an open case, as it may adsorb in di-$\sigma$ or tetra-$\sigma$ bonded configurations, but contrasting evidences have been reported so far, on which of the two is the most stable one and the debate is still open. The adsorption of methanol is less controversial and it is widely accepted it is dissociative with breakage of the O–H at low coverages. But also in this case, investigations are going on to elucidate the adsorption mechanism.

Some people think that carbon and sustainable development are not compatible. This textbook shows that carbon dioxide (CO₂) from the air and bio-carbon from biomass are our best allies in the energy transition, towards greater sustainability. We pose the problem of the decarbonation (or decarbonization) of our economy by looking at ways to reduce our dependence on fossil carbon (coal, petroleum, natural gas, bitumen, carbonaceous shales, lignite, peat). The urgent goal is to curb the exponential increase in the concentration of carbon dioxide in the atmosphere and hydrosphere (Figures 1.1 and 1.2) that is directly related to our consumption of fossil carbon for our energy and materials The goal of the Paris agreement (United Nations COP 21, Dec. 12, 2015) of limiting the temperature increase to 1.5 degrees (compared to the pre-industrial era, before 1800) is becoming increasingly unattainable (Intergovermental Panel on Climate Change (IPCC), report of Aug. 6, 2021). On Aug. 9, 2021 Boris Johnson, prime minister of the United Kingdom, declared that coal needs to be consigned to history to limit global warming. CO₂ has an important social cost…

There are mines of elemental carbon such as graphite. It is the most stable form of elemental carbon at 25°C, under 1 atm (Section 3.7). A second form of pure or nearly pure elemental carbon is represented by diamonds (Section 3.12). Other forms of elemental carbon are produced by combustion or heat treatment of wood (Section 3.6), bio-polymers such as paper, cotton (cellulose), or synthetic polymers such as viscose (Section 11.10.1) and polyacrylonitrile (Section 8.2.7). Nanoparticles such as graphene (Section 3.7), fullerenes (Section 3.8), nanotubes (Section 3.9), and quantum dots of carbon (Section 3.10) are available that find biomedical applications and are used in the manufacture of nanometric objects useful for electronics, optoelectronics, photophysics, energy and the environment protection. Nanoparticles must be handled with care as they can be toxic…

Today, fossil carbon provides us with fuels (energy), polymers (packaging, insulating and building materials, household utensils, glues, coatings, textiles, 3D-printing inks, furnitures, vehicle parts, toys, electronic and medical devices, etc.) and biologically active substances (drugs (Chapter 9), flavorings, fragrances, food additives, plant protection products, etc.). In this chapter we discover the modern materials of our civilization which are very often polymers derived from oil. They are referred to as “plastics” (annual world production: 380 × 10⁶ tons). Their production consumes 8% of the crude oil extracted (ca. 5 billion tons per year). An increasing part of the plastics originates from renewable resources (less than 10% today, see Section 11.10, bio-sourced plastics). Plastics make life easy for us, but at the underestimated cost of damage to our environment (Figure 8.1) and our health. They contaminate the hydrosphere and the agricultural soil. The atmosphere is also contaminated by microplastics…

A new approach for the development of nano-sized spectroscopic-based early-warning sensors using molecular electrostatic potentials (MEP) and molecular vibronics (MV) was presented. The use of MEPs allow us to sense and detect specific molecules in elaborated arrays of logical gates which provide the signature of the trapped species and a decision signal of the results of the sensing operation. Molecular vibronics is used to activate/deactivate, control and program the detection process as well as to transmit the information to and from nano-micro interfaces that allow the interaction with microelectronic systems. In order to develop this scenario, it is needed to explain the exact reasons, from an atomistic point of view rather than using phenomenological models the effects of molecules on nanoclusters. We present here a study of silicon-phenyl complexes.