Molecular Structure and Chemistry of Diamondoids

Journal of Molecular Structure, 2022

The research aimed at the detection of most stable caged diamondoids with varying functional groups, within host MOF by single crystal diffractometer, along with the observation of the trends, for recognition-sites, non-covalent interactions, encapsulation-efficiency, and occupancy of encapsulated diamondoids. The research adopted an optimized experiment and soaking strategy for guest-uptake by crystalline sponge method. Thus, the comparative structure revelation of an analogous-series of cage-compounds, with varying functionalities, in the same Zn-tpt MOF, was the core theme of this paper. In the method, dissolved diamondoids were soaked in the activated crystalline sponge, accredited to the shift of the crystallography study, to a non-crystalline state. MOF was acclimatized to match with the guests, to target the effective capture of diamondoids. Non-covalent capture of easily recognizable, cage-structured molecules was achieved, despite depraved crystal quality, due to strong guest-host interaction in the hydrophobic environment of crystalline sponge. Thus, by sorting the guest and host relation and optimizing the experimental conditions, guests were inserted into the designated MOF.

The Open Organic Chemistry Journal, 2007

Diamond hydrocarbons (or diamondoids) are hydrocarbons that have a carbon skeleton superimposable on the diamond lattice and contain one or more adamantane units. Recently it was found that many higher diamondoids (containing four to eleven adamantane units) are present in petroleum and can be isolated by a series of methods that include HPLC and GC techniques. We develop QSPR equations using molecular descriptors derived from the topology and geometry of diamondoids, by means of dualist graphs consisting of vertices placed at the centers of adamantane cells forming the diamondoid, and of edges connecting vertices centered in adamantane cells sharing faces. From distance (or distancedistance) matrices encoding the topology and geometry of diamondoids one can obtain distance-sums, distance-distance sums, or eigenvectors as molecular descriptors characterizing the diamondoids. These descriptors afford satisfactory correlations with GC and HPLC retention data, and may also facilitate the identification of diamondoid isomers.

Proceedings of the International Congress of Nanotechnology 2005 , 2005

Physical and chemical properties of diamondoids, which are organic compounds with unique structures and properties, are investigated as molecular building blocks (MBBs) for nanotechnology. Some methods and concepts in their role as MBBs in the formation of nanostructures including various aspects of self-assembly are introduced. Those include self-assembly using a solid surface, immobilization techniques for molecules on a solid support, DNA-directed self-assembly, self-assembly in liquid medium, and a host-guest chemistry approach. The applications of diamondoids in host-guest chemistry to construct molecular receptors by self-assembly process are presented. A combined experimental and theoretical effort to investigate the complicated structure-property relation of diamond-like and self-assembling organic nanostructures at the nanoscale level is presented. It is concluded that diamondoids are one of the best candidates for MBBs in molecular nanotechnology to design nanostructures with predetermined physicochemical properties. 2

Proceedings of MRS Fall Meeting, Boston, Mass, Nov. 30-Dec. 2, 2010, 2010

Applying ab initio calculation and molecular dynamics simulation methods, we have been calculating and predicting the essential phase transition and self-assembly of two lower diamondoids (adamantane and diamantane), three of their important derivatives (amantadine, memantine and rimantadine), and two organometallic molecules that are built by substituting one hydrogen ion with one sodium ion in both adamantane and diamantine molecules (ADM • Na and Optimized DIM • Na). To study their self-assembly and phase transition behaviors, we built seven different MD simulation systems, and each system consisting of 125 molecules. We obtained self-assembly structures and simulation trajectories for the seven molecules. Radial distribution function studies showed clear phase transitions for the seven molecules. Higher aggregation temperatures were observed for diamondoid derivatives. We also studied the density dependence of the phase transition which demonstrates that the higher the density-the higher the phase transition points.

Encyclopedia of Nanotechnology, 2009

Diamondoids have been of great interest in recent years due to their role in nanotechnology, drug-delivery and medicine. Due to their six or more linking groups, they have found major applications as templates and as molecular building blocks in nanotechnology, polymers synthesis, drug delivery, drug targeting, DNA-directed assembly, DNA-amino acid nanostructure formation, and in host-guest chemistry. In this paper, the molecular nature of diamondoids, their molecular specificities, their intermolecular interactions and their opto-electronic properties are introduced. These will help in the understanding of the structure-property relations and self-assembly of diamondoids, which is essential for designing functional molecular gears for micro-electro-mechanical systems (MEMS) and sensitive bionanosensors, and for developing new nanodrugs, just to name a few.

European Journal of Organic Chemistry, 2009

Journal of Molecular …, 2006

Nanotechnology Reviews, 2020

Diamondoids are cage-like hydrocarbon materials with unique characteristics such as low dielectric constants, negative electron affinity, large steric bulk, and electron-donating ability. They are widely used for advanced functional materials in nanocomposite science. Surface modification of diamondoids also produces functional derivatives that broaden its applications. This article provides a concise review of the fundamentals of diamondoids, including their origin and functionalization, electronic structure, optical properties, and vibrational characteristics. The recent advances of diamondoids and their derivatives in applications, such as nanocomposites and thin film coatings, are presented. The fabrication of diamondoid-based nanostructured devices, including electron emitters, catalyst sensors, and light-emitting diodes, are also reviewed. Finally, the future developments of this unique class of hydrocarbon materials in producing a novel nanostructure system using advanced nan...

Physics Express, 2011

In this paper, we present quantum mechanical investigations into electronic, structural and intermolecular properties of diamondoids. Diamondoid molecules are cage-like, ultra stable, saturated hydrocarbons. Their basic repetitive unit is a ten-carbon tetracyclic cage system called " adamantine " followed by diamantane, triamantane, tetramantane, etc. They show unique properties due to their exceptional atomic arrangements. Interesting nanotechnology applications are proposed for diamondoid molecules, such as structural components of nanosystems, carriers in drug delivery, their use in formation of self-assembly monolayers and their applications in crystal engineering, to name a few. Quantum mechanical computations are advanced to a level that we can predict properties of diamondoid molecules with unprecedented precision. Initially, we review some recurrent terms in quantum calculations including Hartree-Fock approximation, density functional theory, ab initio calculations and related commercial and developing scientific computer packages. Afterward, we present a number of case studies including electronic and structural properties of diamondoids and their intermolecular interactions. Specifically we review advances made in diamondoids quantum confinement effects, ionization potentials, electronic affinity, quantum conductance and intermolecular interaction between adamantine and AFM tip made up of gold. We also present studies made on functionalized diamondoid molecules (diamondoid derivatives) for possible applications in MEMS and NEMS.

2003

In this report, we describe the first isolation and structural verification of the diamondoid cyclohexamantane, C26H30, a material that has probably never previously existed anywhere in crystalline form. Since the diamond surface can terminate in hydrogen,[1] cyclohexamantane may be thought of as a nanometer-sized diamond of approximately 10 21 carats. In fact, the cyclohexamantane structure has been used to represent a small diamond in theoretical investigations.[2–4] Here we present the experimentally determined properties of cyclohexamantane isolated from petroleum, which includes its single-crystal X-ray structure, and analysis by NMR and laser Raman spectroscopy, as well as mass spectrometry. Diamondoids of the adamantane series are hydrocarbons composed of fused cyclohexane rings, all in stable chair conformations, which form interlocking cage structures that can be superimposed on the diamond crystal lattice.[5] The lower diamondoids have chemical formulas of C4n+6H4n+12, whe...