To determine the normal morphologic evolution of the diaphragm with aging and to correlate age-related changes with other indicators of physical condition--such as skeletal muscle status, obesity, presence of pulmonary emphysema, and presence of esophageal hiatus hernia--a systematic morphometric and morphologic evaluation of computed tomographic studies of 120 patients from the 3d to 8th decades of life was undertaken. Diaphragm muscle thickness did not change significantly with increasing age. Diaphragmatic defects and pseudotumors, nonexistent in the 3d and 4th decades, increased in number and severity to affect 56% of the patients in the 7th and 8th decades. Neither the status of the skeletal muscle nor the presence of obesity correlated with age or with the presence of diaphragmatic defects. Eighty-four percent of the patients with emphysematous changes demonstrated diaphragmatic defects; thus, a strong association with emphysema was observed. If emphysematous patients are excluded, defects were more common in women. The esophageal hiatus width was found to increase with age.

The spin-orbit (SO) effects on the absorption spectra of HMn(CO) 5 and HRe(CO) 5 have been studied by means of ab initio multistate complete active space perturbation second order (MS-CASPT2) and time-dependent density functional theory (DFT) calculations. For both molecules and in contrast to the experimental spectra, the spin-free theoretical absorption spectra differ significantly, especially in the region of the intense band observed at 47,000 cm À1 . The main features of the lowest and highest parts of the absorption spectra are well reproduced making a reasonable assignment of the bands observed at 34,500 and 51,300 cm À1 for HMn(CO) 5 and 37,000 and 50,630 cm À1 for HRe(CO) 5 . Whereas, the lowest band of HMn(CO) 5 has a significant metalcentered (MC) character, the band centered around 37,000 cm À1 in HRe(CO) 5 corresponds to nearly pure metal-to-ligand-charge-transfer (MLCT) states. The intense bands observed above 48,000 cm À1 in both complexes have mixed character with MLCT, sigma bond to ligand charge transfer, sigma bond to sigma bond charge transfer, and metal to sigma bond charge transfer contributions, which may vary as a function of the level of calculation (DFT, MS-CASPT2, SO). This is attributed to the ability of the method at describing electronic correlation effects in various types of excited states in a balanced way. The SO absorption spectra are more realistic for both molecules with a red shift of the start of the absorption and a broadening of the bands due to a large mixing between the singlet-triplet states and an increase of the density of electronic states contributing to the absorption. This red shift is more important in HMn(CO) 5 than in HRe(CO) 5 due to the MC contribution to the lowest states in first-row transition metal complexes. Our calculations point to the presence of an absorption of intermediate intensity, not observed experimentally, around 40,000-42,000 cm À1 , mostly of MLCT character.The geometries of HMn(CO) 5 and HRe(CO) 5 were optimized at the DFT(B3LYP: Becke, three-parameter, Lee-Yang-Parr) level with the LANL2DZ: Los Alamos National Laboratory 2-double-zeta pseudopotential [20] on the rhenium atom and the BRAHIM, DANIEL, AND RAHMOUNI INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY 2091 experimental spectrum of HMn(CO) 5 . The upper states of mixed MSBCT/MLCT/SBSBCT character calculated at 48,150 cm À1 (f ¼ 0.02), 49,680 cm À1 (f ¼ 0.028) and 51,090 cm À1 (0.09) compose the most intense band observed at 51,300 cm À1 .The band observed at 34,500 cm À1 could be attributed to the 1 E (MC/MSBCT) state calculated at 37,130 cm À1 . The region in between 41,000 and 46,820 cm À1 is more difficult to assign. FIGURE 3. Spin-free (dashed lines) and spin-orbit (solid lines) MS-CASPT2 absorption spectra of HMn(CO) 5 (a) and HRe(CO) 5 (b).

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The A ground and the first B excited states of the methylenecyclopropene (triafulvene) are described by localized wave functions, based on 20 structures valence bond structures. The results are compared to CASSCF(4,4) calculations for both the energetics and the dipole moment. Additional calculations with partial electronic delocalization are presented, and it is shown that the dipole moment modification does not correspond to a situation where the antiaromatic situation prevails (with 4n electrons in the cycle). Part of the analysis uses a "trust factor" that helps to decide if a wave function is appropriate to describe a given state. The trust factor compares the VB wave function to the CASSCF's with their overlap. Finally, the valence bond density is used to produce density maps that illustrate the electron transfer upon excitation. Graphical Abstract A projector-based method compares CASSCF wave functions to local wave functions, including Lewis structures as shown in the picture. A "trust factor" (τ) is obtained. Both the ground state and the first excited state of the methylenecyclopropene are discussed.