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The influence of silicon nanocrystal (nc-Si) distributed in the gate oxide on the capacitance is studied for the circumstances that the nc-Si does not form conductive percolation tunneling paths connecting the gate to the substrate, by synthesizing the nc-Si by Si-ion implantation. An excellent agreement is achieved between the MOS capacitance from the modeling and capacitance measurements for several samples, and the influence of implantation energy and implantation dosage on MOS capacitance is studied.

A new value for the proton affinity of C3H6 is offered. The calculation was obtained by pulsed field ionization-photoelectron photoion coincidence spectroscopy.

A new Gaussian-2 method incorporating the energy correction due to spin contamination has been used in studying the structures and energetics of C2H2N and C(sub 2)H(sub 2)N(super +) isomers. The heat of reaction(sub f298) obtained with the new technique shows good agreement with existing data. However, the results for CH2NC and CH(sub 2)NC(super +) as well as for c-NCHCH and c-NCHCH+ do not agree with available experimental data. CH2NC may be the product of the reaction between the nitrogen atom and the vinyl radical based on the ionization energies of the C2H2N isomers.

This paper proposes basis functions based time domain Volterra model for nonlinear system identification. The Volterra kernels are expanded by using complex exponential basis functions and estimated via genetic algorithm (GA). The accuracy and practicability of the proposed method are then assessed experimentally from a scaled 1:100 model of a prototype truss spar platform. Identification results in time and frequency domain are presented and coherent functions are performed to check the quality of the identification results. It is shown that results between experimental data and proposed method are in good agreement.

The Gaussian-2, G2 and G2(MP2) ab initio quantum chemical calculations are suitable for obtaining energy values with 4-5 kcal/mol accuracy for complex sulphur-containing molecular moieties. The stabilities of closed shell molecular species is responsible for the irregular values obtained for various bond dissociation energies. The experimental technique of the calculation is discussed.

A nanocrystal Si (nc-Si) distributed in a narrow layer in the gate oxide close to the gate is synthesized with Si ion implantation and the electrical characteristics of the nc-Si structure are examined. A steplike flatband voltage shift as a function of changing voltage is observed, indicating single electron or hole trapping in the nc-Si at room temperature, whereas the nc-Si structure has shown good charge-retention characteristics.

We have demonstrated the two-color vacuum ultraviolet (VUV)-infrared (IR) photoinduced Rydberg ionization (PIRI) experiment. Trichloroethene (ClCH==CCl[sub 2]) and trans-2-butene (trans-CH[sub 3]CH==CHCH[sub 3]) were prepared in Rydberg states in the range of effective principal quantum number n[sup *]≈7–93 by VUV excitation prior to IR-induced autoionization. The observed VUV-IR-PIRI spectra are found to be independent of n[sup *], suggesting that the electron Rydberg orbital is conserved, i.e., the Rydberg electron is behaving as a spectator during the excitation process. The observed IR active C–H stretching vibrational frequencies ν[sub 12][sup +]=3072±5 cm[sup -1] for ClCH==CCl[sub 2][sup +] and ν[sub 23][sup +]=2908±3 cm[sup -1], ν[sub 25][sup +]=2990±10 cm[sup -1] and ν[sub 30][sup +]=3022±10 cm[sup -1] for trans-CH[sub 3]CH==CHCH[sub 3][sup +] are compared with predictions based on ab initio quantum-chemical procedures and density functional calculations. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

By employing the two-color infrared (IR)-vacuum ultraviolet (VUV) laser photoionization (PI) schemes, we have determined the C[Single_Bond]H stretching frequencies ν[sub 12]=3097.7 cm[sup -1] for trichloroethene (CHCl==CCl[sub 2]) and ν[sub 12][sup +]=3066 cm[sup -1] for CHCl==CCl[sub 2][sup +]. On the basis of the IR-VUV-pulsed field ionization-photoelectron (PFI-PE) measurement, the ratio of the state-to-state PI cross section for CHCl==CCl[sub 2][sup +](ν[sub 12][sup +]=1)←CHCl==CCl[sub 2](ν[sub 12]=1) to that for the formation of the ground state ion from the ground state neutral is determined to be 0.24. The VUV-PI efficiency (PIE) spectrum for CHCl==CCl[sub 2] and IR-VUV-PIE spectrum for CHCl==CCl[sub 2](ν[sub 12]=1) show that the state-to-state PI cross section for the formation of CHCl==CCl[sub 2][sup +] in the ground state from CHCl==CCl[sub 2](ν[sub 12]=1) is ≈0.006 that from CHCl==CCl[sub 2] in its ground state. As expected, the IR-VUV-PIE onset for CHCl==CCl[sub 2](ν[sub 12]=1) exhibits less hot-band tailing than the VUV-PIE onset for supersonically cooled CHCl==CCl[sub 2]. After taking into account the ν[sub 12] frequency, the ionization energy values for CHCl==CCl[sub 2] determined based on the IR-VUV-PIE and VUV-PFI-PE measurements are found to be in excellent agreement. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The single-photon pulsed field ionization photoelectron (PFI-PE) spectrum of trans-2-butene (trans-CH[sub 3]CH=CHCH[sub 3]) in the energy range of 73 500–75 850 cm-1 has been measured using vacuum ultraviolet laser sources. The semi-empirical simulation of fine structures resolved in the original PFI-PE band yields a value of 73 624.7±2.0 cm[sup -1] for the ionization energy (IE) of trans-2-butene. The vibrational bands for trans-CH[sub 3]CH=CHCH[sub 3][sup +] resolved in the PFI-PE spectrum are assigned based on ab initio calculations of the vibrational frequencies and Franck-Condon factors (FCFs) for ionization transitions. This assignment has provided reliable vibrational frequencies (ν[sub 1][sup +]=104 cm[sup -1], ν[sub 2][sup +]=127 cm[sup -1], ν[sub 3][sup +]=131 cm[sup -1], ν[sub 5][sup +]=484 cm[sup -1], ν[sub 8][sup +]=798 cm[sup -1], ν[sub 13][sup +]=1164 cm[sup -1], ν[sub 14][sup +]=1264 cm[sup -1], ν[sub 16][sup +]=1307 cm[sup -1], ν[sub 20][sup +]=1407 cm[sup -1], and ν[sub 22][sup +]=1567 cm[sup -1]) for trans-CH[sub 3]CH=CHCH[sub 3][sup +]. The PFI-PE spectrum is compared to the recently reported PFI-photoion (PFI-PI) spectrum for trans-2-butene. The major difference observed between the PFI-PE and PFI-PI spectra is that the intensities for excited vibrational bands were significantly suppressed or indiscernible in the PFI-PI spectrum, suggesting that the lifetimes for high-n Rydberg states associated with these excited vibrational bands were greatly reduced under the conditions used in the PFI-PI study. The experimental conditions used in the PFI-PI study also led to an IE value of about 20 cm-1 lower than that obtained in the PFI-PE measurement. We have also reassigned the vibrational bands resolved in the PFI-PE spectrum for cis-2-butene based on the FCF calculation and a more reliable set of theoretical vibrational frequencies. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]