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《Solid State Communications》1987,61(4):213-216
IR absorption measurements have been made using a high resolution Fourier-transform spectrometer on crystals of InP in the region of (400–4000)cm-1 at temperature between 11–300k. Very weak, new absorption bands, their absorption coefficients are of ∼10-1cm-1, were observed at 996cm-1, 965cm-1, 932cm-1, 838cm-1, 776cm-1, 742cm-1, 718cm-1, 590cm-1, 558cm-1 and 538cm-1. The frequencies and temperature dependence of these weak bands indicate that they arise from three-phonon processes and appropriate assignments are given. We observed using IR absorption technique for the first time the boron contamination in LEC(B2O3)-CZ InP crystal. The content of boron contamination has been proved to be of ∼1016cm-3. 相似文献
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采用顶部籽晶提拉法,以K2W2O7为助溶剂,生长了Yb:KY(WO4)2新型激光晶体.经热重-差热分析,确定晶体熔点为1045℃,相变温度为1010℃.X射线粉末衍射测试,验证所生长的晶体为β-Yb:KY(WO4)2.晶体结构分析确定Yb:KY(WO4)2晶体由WO6八面体连接而成,WO6八面体是由双氧桥(WOOW)及单氧桥(WOW)构成.晶体粉末样品室温下的红外及拉曼光谱测试,确定WO6原子基团、双氧桥及单氧桥的振动频率.晶体的吸收峰位于940nm,980nm,发射峰位于989nm—1030nm.
关键词:
晶体结构
光谱
晶体生长 相似文献
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所有天然Ia型金刚石红外光谱中都存在3107 cm-1特征峰,而在金属触媒直接合成的金刚石红外光谱中没有检测出3107 cm-1特征峰.本文在6.3 GPa,1500?C条件下,通过Fe70Ni30触媒中添加P3N5直接合成出具有3107 cm-1特征峰的氮氢共掺杂的金刚石.红外光谱分析表明,合成的金刚石中氢有两种存在形式:一种对应着乙烯基团C=CH2中C—H键的伸缩振动(3107 cm-1)和弯曲振动(1450 cm-1)的吸收峰,另一种对应着sp3杂化C—H键的对称伸缩振动(2850 cm-1)和反对称伸缩振动(2920 cm-1)的吸收峰.通过分析发现,3107 cm-1吸收峰与金刚石中聚集态的氮原子有关,当金刚石中没有聚集态的氮元素时,即使氮含量高也不会出现3107 cm-1峰;并且2850和2920 cm-1附近的吸收峰比3107 cm-1附近的吸收峰更为普遍存在.这说明sp3杂化C—H键比乙烯基团的C—H键更广泛存在于金刚石中,从两者的峰值看,天然金刚石中的氢杂质主要以乙烯基团C=CH2存在.3107 cm-1吸收峰与聚集态的氮原子的这种存在关系为天然金刚石形成机制的研究提供了一种新思路,同时较低的合成条件也可能为氢与其他元素共掺杂合成具有n型半导体特性的金刚石提供一个较理想的合成环境. 相似文献
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ir spectra are reported for polycrystalline CsH2PO4 above and below the transformation temperature, 153 K. Three absorption bands at 1760 cm-1 2350 cm-1 and 2800 cm-1 are assigned to -OHO- vibrations. Whilst the 2350 cm-1 band remains essentially unaltered, the 1760 cm-1 band splits into multiplets and the 2800 cm-1 band shifts to lower frequency on cooling below 153 K. A broad band centred at 3240 cm-1 is found to exist in the ferroelectric phase and is associated with the -OHO- mode involving the H(2) proton ordered below the transition. 相似文献
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本文报道用铂丝光热吸收池作为探测器得到了CF3CDCI2的红外多光子吸收谱。并发现在线性吸收谱中944cm-1处的吸收峰在多光子吸收谱中分裂为947cm-1和927cm-1两个吸收峰。这一现象与科里奥利力和非谐性引起的简正振动的耦合作用有关。这样,在用CF3CDCI2/CF3CHCI2体系分离氘同位素时,可以根据这一新结果选择更合适的激发波长。实验还发现在线性吸收谱中986cm-1处的吸收峰在多光子吸收谱中出现约6cm-2的红移。这种红移现象起源于分子振动能级的非谐性。
关键词: 相似文献
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Michael Staak 《Journal of Molecular Spectroscopy》2005,229(1):115-121
The room temperature absorption spectrum of formaldehyde, H2CO, from 6547 to 6804 cm−1 (1527-1470 nm) is reported with a spectral resolution of 0.001 cm−1. The spectrum was measured using cavity-enhanced absorption spectroscopy (CEAS) and absorption cross-sections were calculated after calibrating the system using known absorption lines of H2O and CO2. Several vibrational combination bands occur in this region and give rise to a congested spectrum with over 8000 lines observed. Pressure broadening coefficients in N2, O2, and H2CO are reported for an absorption line at 6780.871 cm−1, and in N2 for an absorption line at 6684.053 cm−1. 相似文献
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The optical absorption, emission, and excitation spectra of CdCl2: Ni2+ single crystals are investigated. The absorption bands around 19,200 cm-1 are reassigned and a few new bands above 22,000 cm-1 are observed and assigned to singlet states. The emission bands at 77 K are examined in more detail and the previous assignments seem to be not correct. 相似文献
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R.W. Patch 《Journal of Quantitative Spectroscopy & Radiative Transfer》1974,14(2):101-110
The coefficient for absorption during H2-H collisions was calculated for temperatures from 2000 to 7000 K and wave numbers between 100 and 40 000 cm-1 for LTE. Because only transitions with Δν = 1 were considered, the absorption was near the fundamental at 4161 cm-1 in the infrared. The model included mechanical anharmonicity, vibration-rotation interaction, excited vibrational states, and transverse components of the dipole moment. At 5500 cm-1, 3750° K, and 1 atm pressure, inclusion of H2-H vibrational absorption increased the absorption of pure hydrogen gas 48 per cent. An approximate formula for the H2-H absorption coefficient is given for rapid calculation. 相似文献
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S. C. Shen Q. L. Jue M. Cardona 《Applied Physics A: Materials Science & Processing》1982,28(4):215-221
The effects of isochronal annealing on the infrared and far-infrared spectra of very heavily B- and P-dopeda-Si(H) are reported. Upon annealing, the B-H stretching mode evolves into two bands centered at 2475 and 2370cm–1. The broad band of the heavily B-doped samples between 600 and 900cm-1 is resolved into three peaks or absorption shoulders located at 830, 725, and 630cm-1. The 640cm-1 band of the heavily P-doped samples splits into two peaks centered at 630 and 670cm-1. The assignment of the above peaks is discussed. The intrinsic infrared absorption due to the Si lattice modes changes only little as a result of the annealing. These changes are a measure of the H-induced ir activity of the Si-Si bands. 相似文献
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《Solid State Communications》1987,63(9):787-791
OH--ions play an important role in the charge compensation of defects in ZnWO4. The interstitial OH in ZnWO4: Fe affects the optical properties, resulting in a sharp symmetric absorption peak at 3445 cm-1 (RT). The substitutional OH in pure ZnWO4 produces a broad absorption band at 3420 cm-1 (RT). The characteristics of both bands are studied at low temperature and in polarized light respectively. The effects induced by the isotopic substitution of H with D are also considered. 相似文献
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Transmission spectra of powdered ferric borate have been measured in the wave number region from 6000 cm-1 to 30 cm-1 at room and liq. N2 temperatures. Eight absorption bands observed are assigned as three A2u and five Eu phonon modes. Of those modes, the temperature dependence of the Eu mode ar 230 cm-1 (300 K) and the A2u mode at 277 cm-1 (300 K) have been measured in the temperature range containing the Néel temperature. They do not show the influence of magnetic ordering. 相似文献
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B.L. Borovich V.S. Zuev D.B. Stavrovsky 《Journal of Quantitative Spectroscopy & Radiative Transfer》1973,13(12):1241-1249
Absorption coefficient κυ for mixtures of Xe (0.2–20 kg/cm2) and Ar (5–40 kg/cm2) has been measured in the range 0.1 cm-1 < κυ < 40 cm-1. Exponential and power dependencies of κυ on wavenumber were observed and are discussed. The κυ-dependencies on the pressure of mixture components are explained by photon absorption at multiparticle collisions of Xe and Ar atoms. 相似文献
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R.K. Hanson J.P. Monat C.H. Kruger 《Journal of Quantitative Spectroscopy & Radiative Transfer》1976,16(8):705-713
Absorption of CO i.r. laser radiation by NO has been studied over the temperature range 300°–4000°K using a grating-tunable CO laser in conjunction with a room-temperature absorption cell and a shock tube. The CO laser line with strongest absorption at elevated temperatures was determined to be the V = 7 → 6, J = 12 → 13 line at 1935.4817 cm-1, which is nearly coincident with the 2ΠV = 0 → 1, J = 37/2 → 39/2 transition in NO. The absorption cell measurements (300°K) were used to infer the position of the NO absorption line (a Λ-doublet at 1935.492 and 1935.497 cm-1) as well as collision-broadening parameters in pure NO and NO dilute in foreign gases: 2γ° (collision-broadened full width at half maximum in cm-1 atm-1 at 300°K) = 0.110, NO-NO; 0.072, NO in Ar; 0.069, NO in Kr; 0.109, NO in N2. Calculations of the NO absorption coefficient at 1935.4817 cm-1 are presented for a range of conditions applicable to current studies in combustion and NOx kinetics. Shock tube measurements (630°–4000°K) supporting these calculations are also reported. 相似文献
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V. V. Apollonov A. A. Pushkar’ T. V. Uvarova S. P. Chernov 《Physics of the Solid State》2008,50(9):1660-1663
The Dy3+ absorption and excitation spectra of BaY2F8 and BaYb2F8 single crystals are investigated in the ultraviolet, vacuum ultraviolet, and visible ranges at a temperature of 300 K. These crystals exhibit intense broad absorption bands due to the spin-allowed 4f-5d transitions in the range (56–78) × 10?3 cm?1 and less intense absorption bands that correspond to the spin-forbidden transitions in the range (50–56) × 10?3 cm?1. The Nd3+ absorption spectra of BaY2F8 single crystals are studied in the range (34–82) × 10?3 cm?1 at 300 K for different crystal orientations. 相似文献
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对一种低温易烧结的Yb:Y2-2xLa2xO3激光透明陶瓷的光谱性能进行了初步研究,Yb:Y2-2xLa2xO3激光透明陶瓷具有宽的吸收带和大的吸收截面,在最强的吸收峰977nm处吸收截面达4.0×10-20cm2;其荧光发射寿命为1.1ms,发射截面在1033nm处为1.0×10-20cm2,在1077nm处为0.7×10-20cm2.Yb:Y2-2xLa2xO3陶瓷的各项光学性能指标接近或达到单晶的指标.
关键词:
氧化镧钇
激光陶瓷
低温烧结
光谱性能 相似文献