Undheim

This characteristic is commonly referred to as the bracketing theorem (E. A. Hylleraas and B. Undheim, Z. Phys. 759 (1930) J. K. E. MacDonald, Phys. Rev. 43, 830 (1933)). These are strong attributes of the variational methods, as is the long and rich history of developments of analytical and computational tools for efficiently implementing such methods (see the discussions of the CI and MCSCF methods in MTC and ACP). 

O. D. Bird, V. Oakes, K. Undheim, and H. N. Rydon, Pleridine Chem., Proc. 

ACS(B)652 O. Thorstad, K. Undheim, R. Lantz, and A.-B. Hdmfeldt, Acta... 

Diazotization of A-heteroaromatic amines may result in hydrolytic opening of the heterocycle, as shown by the examples in Schemes 6-36 and 6-37 which were studied by the group of Ulsaker and Undheim (Hagen et al., 1974 Ranger et al., 1978) and by Davies and Jones (1970). 

Ahmad I, Falck-Pedersen ML, Undheim K (2001) J Organomet Chem 625 160... 

Another example of a twofold metathesis reaction of Undheim s group [248] is the Ru-catalyzed transformation of 6/3-64 to give 6/3-65 in 97% yield (Scheme 6/3.18). 

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