Investigations of nonlinear optical (NLO) properties of Fe, Ru and Os organometallic complexes using high accuracy density functional theory (DFT) calculations

2005 ◽  
Vol 728 (1-3) ◽  
pp. 141-145 ◽  
Author(s):  
Ireshika C. de Silva ◽  
Rohini M. de Silva ◽  
K.M. Nalin de Silva
2021 ◽  
Author(s):  
Azadeh Jamshidi ◽  
Zeinab Biglari

Abstract The effect of alkali metals (Li, Na and K) interaction on the nonlinear optical response (NLO) of Ga12N12 nanocage has been performed using density functional theory (DFT) calculations. The results show that the exo-M@Ga12N12 structures are energetically favorable with negative interaction energies in the range of ‒1.50 to ‒2.28 eV. The electronic properties of decorated structures are strongly sensitive to interaction with the alkali metals. The HOMO-LUMO gap of Ga12N12 is reduced by about 70% due to the decoration with alkali metals. It is obtained that the adsorption of alkali metals over the tetragonal ring of Ga12N12 nanocage remarkably enhances the first hyperpolarizability up to 6.5×104 au. The results display that decorating Ga12N12 nanocage with alkali metals can be introduced it as a novel inorganic nanomaterial with significant NLO properties.


2018 ◽  
Vol 20 (36) ◽  
pp. 23593-23605 ◽  
Author(s):  
C. Ennis ◽  
R. Auchettl ◽  
D. R. T. Appadoo ◽  
E. G. Robertson

The application of high accuracy periodic DFT calculations to replicate laboratory thin film spectra allowing the assignment of vibrational far-infrared modes in nitrile-bearing planetary ices.


2013 ◽  
Vol 68 (12) ◽  
pp. 1356-1370 ◽  
Author(s):  
Hanns-Dieter Amberger ◽  
Hauke Reddmann

The planned model calculations of normal modes of pseudo-trigonal-bipyramidal LaCp3(NCCH3)2 (Cp = η5-C5H5-) (1) adopting density functional theory (DFT), and using the molecular structure as suggested by X-ray investigations, did not converge. Alternatively, DFT calculations assuming molecular C3h symmetry were performed. Unfortunately, these calculations did not reproduce the experimentally derived frequencies of the skeletal modes very well, including a wrong energetic sequence of the four previously unambiguously assigned (close lying) Raman-active ν(La-Cp) skeletal modes. The same presumably also holds for DFT calculations made for LaCp3 · NCCH3 (2) and base-free LaCp3 (3), assuming molecular C3 and C3h symmetry, respectively. In order to check whether the calculated incorrect sequence is produced by the five-membered Cp rings, a DFT calculation also has been performed for the hypothetical model complex [La(η6-C6H6)3]3+ (4) of D3 symmetry. A closer examination of the vibronic sidebands of the hypersensitive absorption transition 4I9/2 → 4G5/2 of [LaCp3(NCCH3)2:Nd3+] (5) showed that first of all, totally symmetric intraligand and not skeletal vibrations are coupling as it was the case for [LaCp3(NCCH3)2:Ln3+] (Ln = Pr, Sm). Applying this result to the vibronic sidebands of some purely electronic crystal field (CF) transitions, which are hampered by strong binary combination vibrations, the energies of these CF levels could be determined. The CF state 1Γ8 of the ground multiplet 4I9/2 of [LaCp3(NCCH3)2:Nd3+], which previously could not be detected by absorption measurements, could be derived from the luminescence transition 4F3/2 → 4I9/2. Considering these additional assignments, the goodness of the fit increased from 32.3 to 29.9 cm-1 for 61 assignments


2018 ◽  
Vol 73 (11) ◽  
pp. 1037-1045 ◽  
Author(s):  
Aijaz Rasool Chaudhry ◽  
Shabbir Muhammad ◽  
Ahmad Irfan ◽  
Abdullah G. Al-Sehemi ◽  
Bakhtiar Ul Haq ◽  
...  

AbstractUsing density functional theory (DFT) methods, we shed light on the structural, optical, electronic, and nonlinear optical (NLO) properties of three derivatives of 9,12-diiodo-1,2-dicarba-closo-dodecaborane(12) (C2H10B10I2). The DFT and time-dependent DFT methods are considered very precise and practical to optimize the ground and excited state geometries, respectively. A vibrant intramolecular charge transfer from highest occupied molecular orbitals (HOMOs) to the lowest unoccupied molecular orbitals (LUMOs) was observed in all compounds. The geometrical parameters of the experimental crystal structure, i.e. bond lengths/angles, have been successfully reproduced. The HOMO and LUMO energies, as well as their energy gaps (Eg), were also calculated and compared with each other for all derivatives. The effect of attached groups on electronic, optical, and NLO properties along with detailed structure-property relationship was discussed. For NLO response, the CAM-B3LYP functional along with relatively larger basis set 6-31+G** (for hydrogen, carbon, boron, and oxygen atoms) and LANL2DZ (for iodine atoms) have been used to optimize the compounds at ground states. The calculation of second-order NLO polarizabilities (βtot) shows that compounds 2 and 3 possess the βtot amplitudes of 3029 and 4069 a.u., respectively, with CAM-B3LYP method that are reasonably larger than similar prototype molecules. Owing to their unique V-shapes, the nonlinear anisotropy values are found to be 0.63, 0.34, and 0.44 for compounds 1–3, respectively, which show the significant two-dimensional character of these compounds. Thus, the NLO amplitudes as well as the nonlinear anisotropies indicate that the above-entitled compounds are good contenders for optical and NLO applications.


2019 ◽  
Vol 18 (11) ◽  
pp. 2759-2765 ◽  
Author(s):  
Claire Tonnelé ◽  
Frédéric Castet

The second-order nonlinear optical properties of 1,3-indandione-derived spirocyclohexadine compounds, a new class of photochromes showing sensitivity to both UV and visible lights, are investigated by means of density functional theory.


2007 ◽  
Vol 06 (03) ◽  
pp. 585-594 ◽  
Author(s):  
YONGQING QIU ◽  
XIAOHONG WANG ◽  
YICHUN LIU ◽  
GUOCHUN YANG ◽  
HUI CHEN

Time-dependent density functional theory (TD-DFT) formalism is employed to calculate the electronic spectra of A 3 B 3 II–VI semiconductor clusters based on the geometrical structures optimized at DFT-B3LYP level. Moreover, their second-order nonlinear optical (NLO) properties are performed by TD-B3LYP combined with sum-over-states (SOS) formula. The calculation results indicate that it is necessary to consider the effective core potential and electron correlation effects when the basis sets are chosen for the heavy atoms. In addition, the results show that the transition energies and HOMO–LUMO gaps of the A 3 B 3 II–VI semiconductor clusters decrease, while the second-order nonlinear optical responses increase with the increasing of VI-group ionic radius. As a result, the SOS formula is valuable to calculate the βμ in the summation of 120 states. Meanwhile, charge transfers from the π bonding to π anti-bonding orbitals between II and VI group atoms significantly contribute to the second-order NLO properties.


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