Infrared spectrum of stannous oxide (SnO)

A tunable diode laser has been used to measure the infrared spectrum of stannous oxide (SnO) in the gas phase between 830 and 868 cm^?1. Measurements of the v = 1-0, 2-1, 3-2, and 4-3 transitions have been made at temperatures ranging from 930 to 1150°C. Over 175 infrared transitions of the nine most abundant SnO isotopic species have been combined with microwave measurements reported by others in a single least-squares analysis of the data to yield a set of eight Dunham coefficients for the X¹Σ⁺ state of SnO. The data have also been fit by a nonlinear least-squares procedure to obtain B_e, ω_e, and the first five Dunham potential constants. The band center for the vibrational transition of ¹²⁰Sn¹⁶O is found at ν₀ (v = 1?0) = 814.70249 ± 0.00027 cm^?1.     

Infrared studies of crystallinity in poly(vinyl chloride)

The infrared spectrum of a solvent-cast film of commercial poly(vinyl chloride) (PVC) can be very sensitively compared to a rapidly quenched film of the same material by using a compensation technique. When this is done, crystalline bands, as seen in urea canal complex PVC, can be detected and measured in the solvent-cast film. The melting and recrystallization behavior as well as the broad melting range from 120° to 210°C indicate the presence of crystallites of widely different degrees of perfection. Crystallization kinetics from the quenched glassy state indicate that time-temperature superposition applies with an activation energy of 90 kcal/mole. Molecular mobility is indicated as the rate-controlling mechanism.     

BCl和Cl2(2A1)的结构与势能函数

采用多种方法,配有多种基组对BCl和BCl2分子的基态蛄构进行优化计算,优选出B3P86/6-311++G(3df)方法时BCl分子进行计算得到基态为X1∑、键长RBCl=0.17159 nm,谐振频率为ωg=837.0003 cm-1;优选出QCISD/6-31G(d,p)方法对BCl2分子进行计算得到基态为X2A1,平衡棱间距RBCl=0.17284 nm、键角βClBCl=125.3466°、离解能Dg=8.0592 eV,并计算出了谐振频率和力常数.在此基础上,运用多体展式理论方法,推导出BCl2分子的解析势能函数,其等值势能面图准确呈现出BCl2分子的蛄构特征及能量变化曲线.由此讨论了Cl+BCl和B+ClCl分子反应的势能面特征.可用于研究该分子的微观反应动力学特性.     

Infrared spectrum and vibrational potential function of thionylimide (HNSO)

The ir absorption of gaseous HNSO, DNSO and H¹⁵NSO is recorded in the range 300–4100 cm^?1 at medium resolution. Besides the fundamental vibrations, overtones and combination bands are measured and assigned. From these data, combined with the ir absorptions of four more isotopic species of thionylimide, and with the centrifugal distortion constants of HNSO and DNSO, a harmonic force field, with 11 constants was derived.     

BCl和BCl2(2A1)的结构与势能函数

采用多种方法,配有多种基组对BCl和BCl2分子的基态结构进行优化计算,优选出B3P86/6-311++G(3df,3pd)方法对BCl分子进行计算得到基态为 、键长 =1.7159nm,谐振频率为 ;优选出QCISD/6-31G(d,p)方法对BCl2分子进行计算得到基态为 ,平衡核间距RBCl=0.17284nm、键角 =125.3466o、离解能 =8.0592eV,并计算出了谐振频率和力常数．在此基础上,运用多体展式理论方法,推导出BCl2分子的解析势能函数,其等值势能面图准确呈现出BCl2分子的结构特征及能量变化曲线．由此讨论了Cl+BCl和B+ClCl分子反应的势能面特征．可用于研究该分子的微观反应动力学特性．     

Internal absorption spectrum of boron doped compensated silicon Si(B,P)

Internal absorption spectrum of boron acceptor impurities in Si(B, P) is investigated at liquid helium temperature. The effect of internal coulomb field, due to the compensation, on the boron internal 2p' line is found to be greater than on the boron external acceptor lines.     

Infrared spectrum and dynamics of the hydrogen bonded dimer (HF)2

We present a brief survey of our investigations of the spectrum of (HF)₂ in the range from 20 to 15000 cm⁻¹. A detailed dicussion of the transition assigned tentatively to the K = 2 → 1 subband of the “torsional” vibration (out-of-plane bending) close to 430 cm⁻¹ is presented. We give a summary of the K-sublevels known to date for all tunneling-vibrational states which have been investigated so far.     

Infrared spectrum of propargylamine

Infrared absorption spectra of propargylamine in the gas phase and in the low-temperature Ar matrix were observed. The vibrational analysis was made with the help of an ab initio MO calculation. A set of effective force constants was derived which reproduces the observed frequencies. The spectrum indicated the occurrence of one rotational isomer, namely trans around the CN bond.     

Phonon spectrum boron nitrideof single-wallednanotubes

Based on a force constant model, we investigated the phonon spectrum and then specific heat of single-walled boron nitride nanotubes. The results show that the frequencies of Raman and infrared active modes decrease with increasing diameter in the low frequency, which is consistent with the results calculated by density functional theory. The fitting formulae for diameter and chirality dependence of specific heat at 300K are given.     

Raman spectrum of single-walled boron nitride nanotube

Using the spectral moments method, the calculations of the Raman spectra of single-walled boron nitride nanotubes (SW-BNNTs) were performed in the framework of the force constants model. Spectra were computed for chiral and achiral nanotubes for different diameters and lengths. The Raman scattering intensities were determined using the bond-polarizability model and a good agreement with group theory analysis was found. We show that the modes in the low frequency region are very sensitive to the nanotube diameter variation, whereas the ones associated to the tangential region are chirality dependent. The number of Raman active modes, their frequencies, and intensities depend on the length of the nanotube.     

Microwave spectrum of fluoroacetyl chloride

The microwave spectrum of fluoroacetyl chloride has been studied in the 8–40 GHz region and transitions arising from one conformer have been assigned. This conformer has all the heavy atoms in a plane with the fluorine and chlorine atoms trans to one another. The rotational constants and nuclear quadrupole coupling constants for the ground vibrational state are (in MHz): H₂FCCO³⁵Cl: A = 9025.82, B = 2403.92, C = 1920.70, χ_aa = ?47.7, χ_bb = 23,7, χ_cc = 24.1; H₂FCCO³⁷Cl: A = 8994.95, B = 2342.24, C = 1879.75, χ_aa = ?38.0, χ_bb = 18.9, χ_cc = 19.1. The spectrum of the first excited torsional state has been assigned. Some lines possibly due to a second conformer have been observed but not yet assigned.     

Infrared laser heterodyne ozone spectrum

An infrared laser heterodyne spectrometer (IRLHS) has been developped for both laboratory and atmospheric studies. A long path and temperature adjustable cell has been designed for laboratory spectra. An ozone spectrum with 5MHz (0.00016 cm^–1) resolution is presented.     

Infrared dispersion of potassium zinc chloride

The infrared reflection spectra for the three main polarizations of K₂ZnCl₄ in the orthorhombic commensurate ferroelectric phase are reported at room temperature. Phonon frequencies are assigned to internal and external modes by comparison with K₂SeO₄ and Rb₂ZnCl₄ data. The dielectric constant along the ferroelectric axis is essentially due to the weight of the low-frequency heavily-damped mode.     

Infrared spectrum of HCN and HCN

The high-resolution spectrum of H¹²C¹⁴N has been measured near 4870 and 6060 cm⁻¹. The following bands have been identified and analyzed: 01¹2-00⁰0, 02⁰2-01¹0, 02²2-01¹0, 04⁰1-00⁰0, 11¹1-00⁰0, 12⁰1-01¹0, and 12²1-01¹0. The C---N stretching fundamental (ν₃) of H¹²C¹⁵N has also been measured near 2100 cm⁻¹. This fundamental is found to be 3 cm⁻¹ higher than previously reported. Other bands that have been identified in the H¹²C¹⁶N spectrum are 03¹0-00⁰0, 04⁰0-01¹0, 04²0-01¹0, and 01¹1-01¹0.     

Low resolution VUV absorption spectrum of boron monoxide

The absorption spectrum of BO has been recorded between 2400 and 300 Å on the SA61 beam line of SUPERACO in Orsay. A new electronic transition has been observed and vibrationally analysed. Nine Rydberg states have been observed and classified into Rydberg series giving two ionization limits at 12.849eV for the X ¹Σ⁺ ionic state and at 13.117eV for the A ¹II state of BO⁺. Two ionization limits have been observed at 754 and 374 Å. The first of these corresponds to the B ¹Σ⁺ state and the last one to the C ¹Σ⁺ state of BO⁺. The new results are compared with the ab initio calculations of Karna and Grein concerning BO and BO⁺. The agreement is satisfactory.     

The millimeter-wave spectrum of methyl chloride

The millimeter-wave spectra of CH₃³⁷Cl in its ground and ν₃ vibrational states, and of CH₃³⁵Cl in its ν₃ state, have been measured and analyzed to give B, D_J, D_JK, and eQq. The values agree well with the less-precise values from high-resolution infrared spectra for the ground state of CH₃³⁷Cl.