Orgel effect

Fig. 17 NEVPT2-based AILFT d-orbital levels schemes in comparison with those from SA-CASSCF for Ni(dtc)2 and Ni(acac)2 reflecting the Orgel effect with dyz > dxz for out-of-phase (dtc-) and the dxz > dyz in-phase (acac ) the energy of dz2 was taken as the energy reference...

Stagnone GJ, Orgel MB, Stagnone JJ (1987) Cardiovascular effects of topical 50% trichloroacetic acid and Baker s phenol solution. J Dermatol Surg Oncol 13 999-1002... 

A further unusual feature of the matrix-dependent polycondensation lies in the character of the nucleobases themselves. Purine mononucleotides undergo polycondensation, in good yields, at complementary matrices consisting of pyrimidine polymers. However, the synthesis of pyrimidine oligonucleotides from their mononucleotides at purine matrices is not effective. This important fact means that a pyrimidine-rich matrix leads to a purine-rich nucleic acid, which is itself not suitable to act as a matrix. This phenomenon also occurs when matrices are used which contain both basic species, i.e., purines and pyrimidines. An increase in the amount of purine in a matrix leads to a clear decrease in its effectiveness (Inoue and Orgel, 1983). However, the authors note self-critically that the condensation agent used cannot be considered to be prebiotic in nature. 

A dominant influence of certain electronic configurations on the structure type is represented by the Jahn-Teller effect (173). It shall be discussed here only briefly. For further information the reader is referred to a review by Or gel and Dunitz (241) and as for the general base of ligand field theory to the books of Orgel (240) and Figgis (101). 

Orgel, L. E. (1952) The effects of crystal fields on the properties of transition metal ions. J. Chem. Soc., pp. 4756-61. 

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