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  2. Wiener index - Wikipedia

    en.wikipedia.org/wiki/Wiener_index

    The Wiener index is named after Harry Wiener, who introduced it in 1947; at the time, Wiener called it the "path number". [2] It is the oldest topological index related to molecular branching. [ 3 ] Based on its success, many other topological indexes of chemical graphs, based on information in the distance matrix of the graph, have been ...

  3. IUPAC numerical multiplier - Wikipedia

    en.wikipedia.org/wiki/IUPAC_numerical_multiplier

    The numbers 200-900 would be confused easily with 22 to 29 if they were used in chemistry. khīlioi = 1000, diskhīlioi = 2000, triskhīlioi = 3000, etc. 13 to 19 are formed by starting with the Greek word for the number of ones, followed by και (the Greek word for 'and'), followed by δέκα (the Greek word for 'ten').

  4. Degree of unsaturation - Wikipedia

    en.wikipedia.org/wiki/Degree_of_unsaturation

    Degree of unsaturation. In the analysis of the molecular formula of organic molecules, the degree of unsaturation (DU) (also known as the index of hydrogen deficiency (IHD), double bond equivalents (DBE), or unsaturation index[1]) is a calculation that determines the total number of rings and π bonds. A formula is used in organic chemistry to ...

  5. Geometry index - Wikipedia

    en.wikipedia.org/wiki/Geometry_index

    Geometry index. In coordination chemistry and crystallography, the geometry index or structural parameter (τ) is a number ranging from 0 to 1 that indicates what the geometry of the coordination center is. The first such parameter for 5-coordinate compounds was developed in 1984. [1] Later, parameters for 4-coordinate compounds were developed. [2]

  6. Hydrophobicity scales - Wikipedia

    en.wikipedia.org/wiki/Hydrophobicity_scales

    Hydrophobicity scales. Hydrophobicity scales are values that define the relative hydrophobicity or hydrophilicity of amino acid residues. The more positive the value, the more hydrophobic are the amino acids located in that region of the protein. These scales are commonly used to predict the transmembrane alpha-helices of membrane proteins.

  7. Impact factor - Wikipedia

    en.wikipedia.org/wiki/Impact_factor

    The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as indexed by Clarivate's Web of Science. As a journal-level metric, it is frequently used as a proxy for ...

  8. h-index - Wikipedia

    en.wikipedia.org/wiki/H-index

    v. t. e. The h-index is an author-level metric that measures both the productivity and citation impact of the publications, initially used for an individual scientist or scholar. The h -index correlates with success indicators such as winning the Nobel Prize, being accepted for research fellowships and holding positions at top universities. [1 ...

  9. Topological index - Wikipedia

    en.wikipedia.org/wiki/Topological_index

    Topological index. In the fields of chemical graph theory, molecular topology, and mathematical chemistry, a topological index, also known as a connectivity index, is a type of a molecular descriptor that is calculated based on the molecular graph of a chemical compound. [1] Topological indices are numerical parameters of a graph which ...