Absorption Spectra Of Naphthalene Research Articles

Modulating molecular plasmons in naphthalene via intermolecular interactions and strong light-matter coupling.

We conducted a theoretical investigation on the modulation of plasmon-like resonances in naphthalene - the so-called molecular plasmons - through intermolecular interactions and strong light-matter coupling. The configuration interaction with single excitations (CIS) approach and its quantum electrodynamics extension (QED-CIS-1) are used to describe the molecular plasmon states under these interactions. We detail the effects of changing intermolecular distances of the naphthalene dimer and incorporating the naphthalene molecule into optical cavities, both allowing for precise control of naphthalene's plasmonic responses. Our results show significant shifts of the plasmon peak in the absorption spectra of naphthalene, depending on the spatial configuration of the dimer and cavity parameters such as polarization, frequency, and coupling strength. Further investigation of the naphthalene dimer in a cavity reveals a synergistic effect on the plasmon peak when the two types of interactions are combined. This research provides insights into the plasmonic behavior of simple polyacenes like naphthalene and opens up possibilities for plasmon modulation in more complex systems.

Fluorescence spectroscopy of naphthalene at high temperatures and pressures: implications for fuel-concentration measurements

Fluorescence of the S 1→S 0 transition of naphthalene vapour after laser excitation at 266 nm was studied in a heated cell. Experiments were carried out for temperature in the range 350–900 K, at pressure between 0.1 and 3.0 MPa and for oxygen molar fraction from 0 to 21%. The absorption cross section of naphthalene showed a non-monotonic dependence upon temperature, which may be attributed to the spectral structures present in the absorption spectrum of naphthalene. Under nitrogen atmosphere, naphthalene fluorescence bi-exponentially decreased by an order of magnitude as temperature increased, whereas it increased by about 10% with pressure. Strong influence of quenching by O2 on naphthalene fluorescence was observed and Stern–Volmer plots were found to be linear for temperatures between 450 and 750 K. The dependence of naphthalene fluorescence on oxygen concentration suggests one to use this molecule for fuel-concentration measurements in turbulent flows.

Calculation of the intensity distribution in the fluorescence and absorption spectra of naphthalene using Osad'ko's method

Calculation of the intensity distribution in the fluorescence and absorption spectra of naphthalene using Osad'ko's method

Electronic transition moments in the spectra of substituted naphthalenes

The absorption spectrum of naphthalene is drastically perturbed as a result of substitution, and the perturbation depends on the nature and position of the substituents (Baba and Suzuki, 1961; Suzuki et al., 1973). In the present communication we report the effect of substitution on the orientation of electronic transition moments in naphthalene. The most reliable experimental method of determining this parameter is based on the rotational contour analysis of the electronic-origin band in the absorption spectrum of molecular vapor recorded under high resolution. This has been done for the near ultraviolet spectra of naphthalene and several of its monoderivatives (Hollas and Thakur, 1973, 1974; Singh and Thakur, 1978). The orientation of the electronic transition moment determined by this method is, however, not unambiguous and one has to choose between the two orientations on the basis of molecular-orbital calculations. The choice of the angle between the transition moment vector and the long in-plane axis of the naphthalene ring in the case of 2-hydroxynaphthalene (Hollas and Thakur, 1973) was made on the basis of the MO calculations of Nishimoto (1967). The orientation angle rejected on this basis is, however, found to be in good agreement with a later MO calculation of Suzuki et al. (1973). This ambiguity between the two different sets of calculations is resolved if we remember that the transition moment is represented by a double-headed arrow and that the MO calculations give either the acute or the obtuse angle between this arrow

Absorption spectrum of naphthalene in rare-gas matrices

The absorption spectrum of naphthalene has been studied in rare-gas matrices (RGM). Molar extinction coefficients have been determined and oscillator strengths of various π ∗-π transitions deduced. Bands in the 6.5 to 7.1 eV region, some of which were previously observed and interpreted as members of an impurity exciton (Rydberg) series, have been assigned to a π ∗-π transition. The results are compared with the theoretical prediction.

Features of fluorescence and absorption spectra of naphthalene and its deutero derivatives (under Shpol'skii-effect conditions)

The fluorescence and absorption spectra of naphthalene in different aggregate states have been investigat~ed on many occasions [1-5], but they cannot be regarded as fully interpreted. In an analysis of later experimental data, the Herzberg--Teller mechanism of vibronic interaction was introduced to explain the fluorescence spectrum of naphthalene [5]. An investigation of the intensity distribution [6] showed the absence of mirror symmetry between the fluorescence and absorption spectra in the region of the first electronic transition.

Anisotropy of the T-T absorption spectra of naphthalene and phenanthrene

The naphthalene absorption in the spectral region of 3500–4100 Å consists of two perpendicularly polarized band systems. This can be shown by polarization measurements. The arguments given do not allow a decision as to whether or not the short axis polarized band is the 3A g − ← 3B iu + transition or an induced vibronic band of the 3B 3g − ← 3B iu + transition generated by a b 3g vibration mode. The T-T polarization of phenanthrene as a function of the excitation wavenumber is quantitatively compared with the equivalent S 1 ← S 0 fluorescence polarization. There is a good agreement between the calculated and the measured curve.

Matrix effect on the linewidth of the 3B 2u+ - 3B 1g− absorption spectrum of naphthalene

The shape and linewidth of the triplet-triplet absorption of naphthalene in durene and in perdeuterated naphthalene, as well as of naphthalene X-traps, have been analyzed. It is found that the observed lines are lifetime broadened and that relaxation of the superexcited triplet state is intra- and intermolecular.

Geometrical Structures of Excited States of Conjugated Molecules. II. The Calculated Vibronic Intensity Distributions in the Absorption Spectra of Naphthalene

Abstract The normal coordinates and the vibrational frequencies in the first excited singlet (1B2u), the second excited singlet (3B1u), and the first excited triplet (3B1u) states of naphthalene, whose geometries were calculated by a semiempirical method, are evaluated by assuming a simplified valence force field. The relation between the normal coordinates of two different electronic states is expressed on the basis of the Franck-Condon principle. The mixing among the excited-state normal coordinates, expressed in terms of the ground-state normal coordinates, is neglected in the present treatment. By using the simple relation between the normal coordinates of two different electronic states, the vibronic intensity distributions in the absorption spectra (1B2u←1Ag, 1Lb, 1B1u←1Ag, 3La, and 3B1u←1Ag,3La) have been calculated. The vibronic intensity distribution of the 1B2u←1Ag transition has been calculated, taking into consideration the intensity of the interpenetrating sets of the vibronic band groups on the basis of the Herzberg-Teller perturbation theory.

Triplet‐Triplet Absorption Spectra of Aromatic Hydrocarbons: I. Naphthalene

AbstractThe difference between the triplet‐triplet and singlet‐singlet absorption spectrum of naphthalene has been measured at 90°K using a newly developed computer controlled spectrograph. Good spectral resolution has been obtained and a strong band was found in the ultraviolet region. Recent calculations are compared with the triplet‐triplet spectrum of naphthalene.

Observation and Interpretation of Triplet-Triplet Absorption Spectra of Substituted Naphthalenes

Abstract Triplet–triplet (T–T) absorption spectra of naphthalene, α- and β-methoxynaphthalene have been observed in rigid-glass solutions at 77°K by the rapid-scan spectrophotometric method and in fluid solutions at room temperature by the flash spectroscopic method. Hydrogenbonding effects on the T–T absorption spectra were examined for α- and β-naphthol. α-Naphthol was found to give different absorption spectra, depending upon the solvents employed. In a certain case the spectrum is attributed to a photoproduct rather than to the triplet state of a-naphthol. Analysis of the spectral data leads to the conclusion that the T–T absorption spectra in α-derivatives involve two different electronic transitions, and those in β-derivatives are due to a single electronic transition which is analogous to the transition in naphthalene. In agreement with these observations, calculations performed by the Pariser-Parr-Pople method predict that in the low-energy region, α-naphthol should have two allowed and detectable transitions, 3Ψ1→3Ψ7 and 3Ψ1→3Ψ8, and naphthalene and β-naphthol have only one such transition, 3Ψ1→3Ψ9. The wave functions of triplet states are subjected to configuration analysis, with the result that 3Ψ7 and 3Ψ8 of α-naphthol are related predominantly to 3Ψ8 and 3Ψ9 of naphthalene, respectively.

Infrared absorption spectra of naphthalene and anthracene anion-radicals

The infrared spectra of naphthalene and anthracene anion-radicals and their completely deuterated analogs have been studied. The most intense bands have been assigned, and it has been shown that the frequencies of the bending and stretching vibrations of the ring and the C-H (D) bond are less than the corresponding frequencies for the hydrocarbons. The decrease in the frequencies has been attributed to the fact that the unpaired electron of the anionradical, present in an antibonding orbital, decreases the force constants of the bonds; this is analogous to an excited state of the hydrocarbon molecule. A product rule has been proposed for the anion-radicals and their original hydrocarbons.

Absorption spectra in the vacuum ultraviolet and the ionization potentials of naphthalene and naphthalene-d8 molecules

The vapour absorption spectra of naphthalene and naphthalene-d8 were obtained photographically and photoelectrically from 50000 to 70000 cm-1. A series of Rydberg transitions and possibly two π*-π systems are observed. Each of the five Rydberg series converges to an ionization potential of 65620 � 40 cm-l, i.e. 8.136 � 0.005 eV (C10H8), and 65640 � 60 cm-l, i.e. 8.138 � 0.008 eV (C10D8). The quantum defects of the series are (0.94, 0.88, 0.82, 0.67, 0.53) � 0.01. The significance of these results is discussed.

Asymmetric annellation effects—VI

Strong constant spectral shifts are recorded as stated in the preceding chapters when benzene rings are fused together to form the acene or phene series. These shifts are constant and from them an order number K or K p for each member in the annellation series may be derived. In striking contrast to this, very different spectral shifts are produced by the successive connection of two diphenyl systems to benzene (I) forming triphenylene (II) and tetrabenzanthracene (III), which is formally a symmetric annellation. The first shift is much bigger than the second one. The nature of this electronic asymmetry becomes obvious if the second shift is deducted from the β-band (in √A) of triphenylene (II). This means the elimination of the influence of the angular rings. The result is a β-band at 2237 A, which is almost identical with the β-band found in the absorption spectrum of naphthalene which is at 2210 A in alcoholic solution. It is obvious that one of the two annellations produces an induced benzenoid ring, marked “Bz”, and extends the central aromatic system of the benzene ring to a naphthalene system, whilst the second annellation does not extend it to an anthracene system but forms an empty ring, marked “E”. It must be concluded therefore that each inherent benzenoid ring (as indicated by the circles) can transfer two π-electrons only to the induced benzenoid ring (Bz), a conclusion which was reached in the preceding chapters for different reasons. It appears that the formation of an induced π-electron sextet (Bz) has preference over a symmetric distribution of π-electrons. If this interpretation is correct then the same principle should apply to the central acene system in a higher tetrabenzacene, without regard to the number of rings. There is only one sextet in an acene independent of its length and accordingly only two transferable π-electrons able to migrate from one ring to the other.

Excited States of the Naphthalene Molecule. II. Further Studies on the First Singlet—Singlet Transition

The polarized fluorescence and absorption spectra of naphthalene and naphthalene d-8 have been studied under the conditions described in Part I for the absorption of ordinary naphthalene. When all the data are examined and compared with the Raman assignments, a complete set of totally symmetric fundamentals for the first excited state can be found. The b1g-modes which bring about the short-axis absorption of naphthalene may be combinations rather than fundamentals. The short-axis fluorescence shows that b1g-combinations rather than fundamentals bring about vibrational-electronic interaction, yet most of the short-axis fluorescence has ag-origins. This latter fact is not completely understood, although partial explanations are offered. It is deduced from the vibrational pattern of the absorption and emission spectra that a change in length of the central link and a slight expansion of the rings are the most important geometry changes occurring in the transition to the first excited state. The symmetry in this state remains D2h.

The near-ultra-violet absorption spectra of naphthalene and its monohalogen derivatives in solution

Download options Please wait... Article information DOI https://doi.org/10.1039/JR9540000304 Article type Paper Download Citation J. Chem. Soc., 1954, 304-311 BibTex EndNote MEDLINE ProCite ReferenceManager RefWorks RIS Permissions Request permissions The near-ultra-violet absorption spectra of naphthalene and its monohalogen derivatives in solution J. Ferguson, J. Chem. Soc., 1954, 304 DOI: 10.1039/JR9540000304 To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page. If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given. If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page. Read more about how to correctly acknowledge RSC content. Search articles by author J. Ferguson

195. Chromophoric groups. Part II. Absorption spectra of naphthalene, hydronaphthalenes, and related compounds

The first page of this article is displayed as the abstract.

The Infra-Red Absorption Spectrum of Naphthalene and of Some of its Mono-Derivatives in Solution

The Infra-Red Absorption Spectrum of Naphthalene and of Some of its Mono-Derivatives in Solution