Haaland model

According to the Haaland model, an increase of the Lewis acid-base interaction is accompanied by a decrease of both the R—Al—R bond angles and the Al—R bond distances. However, comparisons are possible only for adducts containing the same alane to exclude any steric or electronic effects of... 

It was on this background that Haaland et al. reinvestigated the beryllocene stmcture by electron diffraction. They again confirmed the compatibility of the Csv model with the experimental data. However, they also found a slip model by moving the ring at the longest distance from the metal atom sideways to about 0.8 A. The notion of large-amplitude motion is also consistent with the experimental data. 

R.D. Guenard, C.M. Wehlberg, R.J. Pell and D.M. Haaland, Importance of prediction outlier diagnostics in determining a successful inter-vendor multivariate calibration model transfer, Appl. Spectrosc., 61, 747 (2007). 

David Haaland et al. added to the modeling literature with a 1992 paper [9]. This work used whole blood for the model. Scanning from 1500 to 2400 nm, a PLS equation was developed on glucose-spiked whole blood. The range between 0.17 and 41.3 mM yielded an equation with a standard error of 1.8 mM. Four patients were used as models for this project. Cross-validated PLS standard errors for glucose concentration based on data obtained from all four subjects were 2.2 mM. 

Davidian and Haaland (1990) call this a components of variance model because is the variance component from the detector when no analyte is present and f(x 0)4>2 is the variance component from the analyte response. Residual variance models can be empirically determined by trial and error, and indeed most are chosen in this manner, but hopefully they will be selected based on the scientist s knowledge of the process. A full description of variance model estimation is made in Davidian and Carroll (1987) and Carroll et al. (1988). 

O Connell, M.A., Belanger, B.A., and Haaland, P.D. (1993) Calibration and assay development using the four parameter logistic model. Chemometrics and Intelligent Laboratory Systems, 20, 97 114. 

Haaland A (2008) Molecules and models. Oxford University Press, Oxford... 

Haaland A (2008) Molecules and models. Oxford University Press, Oxford, pp 205-206 Haaland A, Green JC, McGrady GS, Downs AJ, Gullo E, Lyall MJ, Timberlake J, Tutukin AV, Volden HV, 0stby K-A (2003) Dalton Trans 4356-4366... 

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