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  2. Curtin–Hammett principle - Wikipedia

    en.wikipedia.org/wiki/Curtin–Hammett_principle

    The Curtin–Hammett principle is a principle in chemical kinetics proposed by David Yarrow Curtin and Louis Plack Hammett.It states that, for a reaction that has a pair of reactive intermediates or reactants that interconvert rapidly (as is usually the case for conformational isomers), each going irreversibly to a different product, the product ratio will depend both on the difference in ...

  3. Forbidden mechanism - Wikipedia

    en.wikipedia.org/wiki/Forbidden_mechanism

    In spectroscopy, a forbidden mechanism (forbidden transition or forbidden line) is a spectral line associated with absorption or emission of photons by atomic nuclei, atoms, or molecules which undergo a transition that is not allowed by a particular selection rule but is allowed if the approximation associated with that rule is not made. [1 ...

  4. Reaction progress kinetic analysis - Wikipedia

    en.wikipedia.org/wiki/Reaction_progress_kinetic...

    c) The rate of reaction progress (product formation) is monitored over time by methods such as reaction progress calorimetry or may be obtained by taking the first derivative of (a). d) Describing the rate of reaction progress with respect to consumption of starting material spreads the data into a more informative distribution than observed in ...

  5. Group-contribution method - Wikipedia

    en.wikipedia.org/wiki/Group-contribution_method

    The simplest form of a group-contribution method is the determination of a component property by summing up the group contributions : [] = +.This simple form assumes that the property (normal boiling point in the example) is strictly linearly dependent on the number of groups, and additionally no interaction between groups and molecules are assumed.

  6. Woodward–Hoffmann rules - Wikipedia

    en.wikipedia.org/wiki/Woodward–Hoffmann_rules

    Thermolysis converts 1 to (E,E) geometric isomer 2, but 3 to (E,Z) isomer 4.. The Woodward–Hoffmann rules (or the pericyclic selection rules) [1] are a set of rules devised by Robert Burns Woodward and Roald Hoffmann to rationalize or predict certain aspects of the stereochemistry and activation energy of pericyclic reactions, an important class of reactions in organic chemistry.

  7. Benson group increment theory - Wikipedia

    en.wikipedia.org/wiki/Benson_group_increment_theory

    The total calculations add to −5.15 kcal/mol (−21.6 kJ/mol), which is identical to the experimental value, which can be found in the National Institute of Standards and Technology Chemistry WebBook. [15] Diogo and Piedade used BGIT to confirm their results for the heat of formation of benzo[k]fluoranthene.

  8. List of chemistry mnemonics - Wikipedia

    en.wikipedia.org/wiki/List_of_chemistry_mnemonics

    A mnemonic is a memory aid used to improve long-term memory and make the process of consolidation easier. Many chemistry aspects, rules, names of compounds, sequences of elements, their reactivity, etc., can be easily and efficiently memorized with the help of mnemonics.

  9. Pushforward measure - Wikipedia

    en.wikipedia.org/wiki/Pushforward_measure

    The previous example extends nicely to give a natural "Lebesgue measure" on the n-dimensional torus T n. The previous example is a special case, since S 1 = T 1. This Lebesgue measure on T n is, up to normalization, the Haar measure for the compact, connected Lie group T n.