Andre E. Kemeny

Accurate ab initio study of the energetics of phosphorus nitride: Heat of formation, ionization potential, and electron affinity

High level ab initio electronic structure calculations at the coupled cluster CCSD(T) level with augmented correlation-consistent basis sets extrapolated to the complete basis set limit have been performed on PN, PN+, and PN−. The geometries were optimized up through the aug-cc-pV5Z level and vibrational frequencies were calculated with the aug-cc-pVQZ basis set. The heat of formation of PN at 0 K is predicted to be 43.7±0.9 kcal/mol and is within the error limits of the revised experimental value at 41.2±3.6 kcal/mol. The calculated adiabatic ionization potential is 11.90±0.05 eV as compared to the experimental value of 11.88±0.01 eV and the calculated adiabatic electron affinity is 0.126±0.01 eV as compared to the experimental value of 0.32±0.20 eV.

Structures and heats of formation of the neutral and ionic PNO, NOP, and NPO systems from electronic structure calculations

High level ab initio electronic structure calculations using the coupled cluster CCSD(T) method with augmented correlation-consistent basis sets extrapolated to the complete basis set limit have been performed on the PNO, NOP, and NPO isomers and their corresponding anions and cations. Geometries for all species were optimized up through the aug-cc-pV(Q+d)Z level and vibrational frequencies were calculated with the aug-cc-pV(T+d)Z basis set. The most stable of the three isomers is NPO and it is predicted to have a heat of formation of 23.3 kcal/mol. PNO is predicted to be only 1.7 kcal/mol higher in energy. The calculated adiabatic ionization potential of NPO is 12.07 eV and the calculated adiabatic electron affinity is 2.34 eV. The calculated adiabatic ionization potential of PNO is 10.27 eV and the calculated adiabatic electron affinity is only 0.24 eV. NOP is predicted to be much higher in energy by 29.9 kcal/mol. The calculated rotational constants for PNO and NPO should allow for these species to be spectroscopically distinguished. The adiabatic bond dissociation energies for the P[Single Bond]N, P[Single Bond]O, and N[Single Bond]O bonds in NPO and PNO are the same within approximately 10 kcal/mol and fall in the range of 72-83 kcal/mol.

Heel and Calf Capillary-Support Pressure in Lithotomy Positions

• A THREE-PART ANALYSIS was undertaken to increase understanding of the occurrence of pressure ulcers in lithotomy positions. An innovative measuring device was used to determine capillary pressure. • ANKLE BLOOD PRESSURE was measured compared to ankle height in 11 participants. Ankle systolic and diastolic pressure decreased approximately 20 mmHg per foot of elevation. • CALF AND HEEL CAPILLARY-SUPPORT pressures were measured in 15 participants in the standard lithotomy position. Capillary-support pressure for the calf was substantially less than for the heel. • HEEL CAPILLARY-SUPPORT PRESSURES were measured in 16 participants in the high lithotomy position. As heel height increased, capillary-support pressure also increased. AORN J 81 (April 2005) 821–830.

CPR Degradation Diagram

During untreated ventricular fibrillation (VF), before CPR is applied, different bodily systems deteriorate at different rates. This paper describes the times when the EEG disappears, when respiratory arrest occurs, and when PD-PEA occurs. It also describes the frequency of VF waves over a 7-min period and how the frequency increases with good CPR.