The high-order optical nonlinearity of 2,11,20,29-tetrabromo-2,3-naphthalocyanine iron

2018 ◽  
Vol 22 (09n10) ◽  
pp. 863-867
Author(s):  
Wang Zhang ◽  
Chunying He ◽  
Lining Zhang ◽  
Li Jiang ◽  
Yijun Yuan ◽  
...  

A novel naphthalocyanine 2,11,20,29-tetrabromo-2,3-naphthalocyanine iron was synthetized. Its optical nonlinearity was investigated using the Z-scan technique. Reverse saturable absorption and high-order optical nonlinear refraction were detected. The absorption cross sections of the ground state, the singlet first excited state and the triplet first excited state were fitted to be 3.2 × 10[Formula: see text] cm[Formula: see text], 6.2 × 10[Formula: see text] cm[Formula: see text] and 4.6 × 10[Formula: see text] cm[Formula: see text], respectively. Fits also gave 1.17 × 10[Formula: see text] cm[Formula: see text] for the refractive volume of the ground state, 0.6 for the ratio of the refractive volume of the singlet first excited state to the ground state and 2.7 for the ratio of refractive volume of the first triplet excited state to the ground state.

2000 ◽  
Vol 09 (04) ◽  
pp. 505-521 ◽  
Author(s):  
J. CALLAGHAN ◽  
W. J. BLAU ◽  
F. Z. HENARI

Investigations of the reverse saturable absorption behaviour of Fullerenes C 60 and C 70 and some of their Pt and Pd metal derivatives have been carried out with picosecond pulses at 532 nm. From intensity dependent transmission measurements, coupled with a population level kinetic analysis, excited state cross sections were determined for the materials. These show that C 60 possesses the largest excited state to ground state cross-section ratio and that, of the materials studied, it offers the best optical limiting ability around 532 nm. C 70, due to its large ground state absorption, has been shown not to be an efficient limiter. The metal derivatives perform better than C 70 but less efficiently than C 60.


2016 ◽  
Vol 18 (41) ◽  
pp. 28674-28687 ◽  
Author(s):  
Taotao Lu ◽  
Chengzhe Wang ◽  
Levi Lystrom ◽  
Chengkui Pei ◽  
Svetlana Kilina ◽  
...  

Extending the acetylide ligand π-conjugation diminishes the terminal substituent effect on the lowest excited states, but expands the triplet excited-state absorption to the near-IR region.


2021 ◽  
Author(s):  
Cuifen Lu ◽  
Taotao Lu ◽  
Peng Cui ◽  
Svetlana Kilina ◽  
Wenfang Sun

Dinuclear Ir(iii) complexes tethered by fluorenyl motif exhibited weak 1,3MLCT/1,3LLCT absorption at >500 nm, dual phosphorescence, broad triplet excited-state absorption, and reverse saturable absorption at 532 nm.


2019 ◽  
Vol 11 ◽  
Author(s):  
G. Kalliabakos ◽  
S. Kossionides ◽  
P. Misailides ◽  
C. T. Papadopoulos ◽  
R. Vlastou

A combination of nuclear reaction analysis (NRA) and Rutherford backscattering spectroscopy (RBS) were utilized in order to obtain information on the depth distribution of sulphur and copper in artificially produced and natural patina layers. The copper profiling was performed by using the reaction 63Cu(p,p'y)6 3Cu and detecting the 1327 keV γ-ray deexciting the third excited state to the ground state of 6 3Cu produced. For the determination of sulfur the 2230 keV γ-ray was used, deexciting the first excited state to the ground state of 32S formed through the reaction 3 2S(p,p'y)3 2S, which exhibits three sharp resonances at projectile energies 3.094, 3.195 and 3.379 MeV. The relevant cross-sections were measured in the energy range between 3.0 and 3.7 MeV in steps of 20 keV at 125° to the incident proton beam direction. Supporting information on the depth distribution of oxygen and the other elements of the patina samples was obtained by p-RBS (Ep = 1.5 MeV; θ = 160°).


1977 ◽  
Vol 55 (5) ◽  
pp. 428-433 ◽  
Author(s):  
H. Ferdinande ◽  
N. K. Sherman ◽  
K. H. Lokan ◽  
C. K. Ross

Photoneutron energy spectra from 7Li have been measured by time-of-flight methods, for bremsstrahlung end-point energies increasing in 2 MeV steps from 13 to 25 MeV. The ground-state and approximate first-excited-state differential cross sections at 90° have been obtained from 8.5 to 23 MeV. No pronounced fine structure has been observed. The measured branching ratio to the first excited state falls from an average value of 0.70 between 10.3 and 14.5 MeV to an average of 0.29 between 14.5 and 18 MeV, and rises again to an average of 0.38 between 18 and 23 MeV. This behaviour can be explained by a crude theoretical model in which 1p → 2s and 1p → 1d single particle transitions dominate below 18 MeV. The calculation predicts a branching ratio of 0.50 near threshold, falling to 0.23 at higher energies, in reasonable agreement with the experiment. The integrated value of the ground-state cross section up to 23 MeV is about (38.7 ± 3.9) MeV mb, while that for the first excited state is about (17.2 ± 3.4) MeV mb. Together they account for 39% of the exchange-augmented dipole sum of 7Li.


2003 ◽  
Vol 12 (03) ◽  
pp. 367-376 ◽  
Author(s):  
G. A. KUMAR

Nonlinear optical response and reverse saturable absorption behavior of various rare earth phthalocyanines such as Nd , Eu , Sm and La in dimethyl formamide (DMF) solution were studied under high power Nd:YAG laser excitation. Excited state absorption cross-sections and two-photon absorption cross-sections of these systems are measured from the limiting characteristics. The SmHPc 2 system yields maximum value for excited state absorption cross-section and its potential application in DMF as a suitable optical limiter is also discussed.


1975 ◽  
Vol 53 (8) ◽  
pp. 786-794 ◽  
Author(s):  
J. D. Allan ◽  
J. W. Jury ◽  
R. G. Johnson ◽  
K. G. McNeill ◽  
J. G. Woodworth ◽  
...  

Photoneutron energy spectra from 18O have been measured by time-of-flight spectroscopy at bremsstrahlung endpoint energies from 11 to 18 MeV in 1 MeV steps to obtain the (γ, n0) and (γ, n1) differential cross sections. The ground state photoneutron cross section contains at least 8 major resonances in the region from 10 to 17 MeV and has an average value of 100 μb/sr. The cross section to the first excited state of 17O contains only two major resonances, at 11.4 and 14.4 MeV, and the average cross section in the region from 11 to 16 MeV is about 40 μb/sr. Of particular interest is a resonance at 14.4 MeV which appears to reflect a simple excitation of one of the valence neutrons to the 2p3/2 state. Analysis of the (γ, n0) and (γ, n1) cross sections for this continuum state leads to estimates of the configuration amplitudes of the 2s1/2 and 1d5/2 components of this state to be 0.62 ± 0.06 and 0.78 ± 0.08 respectively and the ratio of the (2s1/2)2 to (1d5/2)2 amplitudes in the ground state of 18O to be 0.39 ± 0.02.


2018 ◽  
Vol 27 (01) ◽  
pp. 1850001
Author(s):  
Feng Wu ◽  
Shunlong Zhao ◽  
Siwen Zhang ◽  
Jiang Lv

The nonlinear optical (NLO) properties of P3HT in orthodichlorobenzene were investigated at 532[Formula: see text]nm by Z-scan technique in the nanosecond domain. The nonlinear refraction of P3HT solution is up to an order of 10[Formula: see text][Formula: see text]esu and changes the sign from positive to negative with an increase in the input intensity. The reverse saturable absorption of the P3HT solution was observed in the intensity range of the measurements and their nonlinear absorption coefficient reaches an order of 102[Formula: see text]cm/GW. The strong optical nonlinearity perhaps allows them to be widely applied in the photoelectric field.


2017 ◽  
Vol 16 (06) ◽  
pp. 1750048
Author(s):  
Mohammad Mostafanejad

We review the fundamental ideas of free complement (FC) method through its application on both ground and first excited states of helium atom. We have found that lower energies can be obtained with fewer number of terms in the FC expansion of the ground state wavefunction. In this case, the optimization of orbital exponents was not necessary for achieving spectroscopic accuracy, especially at higher orders where the structure of the FC wavefunction converges to that of the exact one. We have discovered that permanents naturally appear in the FC expansion of the first triplet excited state wavefunction. Including permanents in the FC expansion is shown to be energetically important for the first triplet excited state of helium atom whereas it is not computationally favorable at higher orders. Finally, considering the group theoretical properties of the symmetric group [Formula: see text] and using immanants, a compact and more elegant form for the FC expansion of the first triplet excited state of the helium atom is achieved.


1970 ◽  
Vol 48 (1) ◽  
pp. 35-45 ◽  
Author(s):  
O. Häusser ◽  
B. W. Hooton ◽  
D. Pelte ◽  
T. K. Alexander ◽  
H. C. Evans

The reorientation effect in Coulomb excitation with 62 MeV 35Cl projectiles was used to measure the static quadrupole moment of the first excited state in 24Mg. From a comparison of the inelastic scattering cross sections at CM scattering angles of 123.1° and 72.8°, a static quadrupole moment of Q = −0.243 ± 0.035 b was deduced. The E2 matrix element connecting the ground state and first excited state was also measured and corresponds to 20.3 ± 1.4 W.u. for the 2+ → 0+ transition. The results are compared with predictions of the rotational model.


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