Physical Sciences and Mathematics Commons^™

Concepts And Implications Of Interactive Recovery, Robert F. Gordon Ph.D., George B. Leeman Jr, Clayton H. Lewis

Faculty Works: MCS (1984-2023)

RC 10562 (#47293)

When working interactively on the computer, it is valuable to be able to undo a series of commands in order to return to a previous state. We identify contradictions and limitations in the basic concepts of undo. We introduce three types of undo functions with which we examine the characteristics of undo, explain these limitations, and determine the minimum requirements for a recovery facility. Then we discuss the implications of undo for user interfaces and suggest au.xiliary functions to display and simplify the resulting history structure and to view and recover prior states.

Theoretical Study Of H2o–Hf And H2o–Hcl: Comparison With Experiment, M. M. Szczesniak, Steve Scheiner, Y. Bouteiller

Chemistry and Biochemistry Faculty Publications

The H bonds in H₂O–HF and H₂O–HCl are studied and compared using ab initio molecular orbital methods and the results compared to experimental data. Basis sets used are: (i) triple valence 6‐311G∗∗ and (ii) double ζ with two sets of polarization functions. Electron correlation, included via second‐ and third‐order Møller–Plesset perturbation theory, is found to have profound effects on both systems, particularly H₂O–HCl. Both H bonds are strengthened substantially with a concomitant reduction in length. H‐bond energies and geometries calculated at correlated levels are in excellent accord with …

Ab Initio Study Of Fh–Ph3 And Clh–Ph3 Including The Effects Of Electron Correlation, Z. Latajka, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

Ab initio calculations are carried out for FH–PH₃ and ClH–PH₃ using a basis set including two sets of polarization functions. Electron correlation is incorporated via Møller–Plesset perturbation theory to second and (in part) to third orders. The basis set is tested and found to produce satisfactory treatments of subsystem properties including geometries and dipole moments as well as the proton affinity and inversion barrier of PH₃. Electron correlation is observed to markedly enhance the interaction between PH₃ and the hydrogen halides. Its contribution to the complexation energy is 30% …