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Theoretical investigations of the auxochromic effect on novel thermally activated delayed fluorescence (TADF) anthracene derivatives

BMC Chemistry volume 19, Article number: 41 (2025) Cite this article

Abstract

Thermally active delayed fluorescence (TADF) of experimentally synthesized anthracene derivatives is studied. The studied compounds are named as 9-cyano-10-diphenylamino-anthracene (Cy-Anth-1), 9-(N-carbazolyl)-10-cyanoanthracene (Cy-Anth-2), 10-(benzofuro[2,3-b] pyridin-6-yl)-N, N-diphenylanthracen-9-amine (Benzo4-Anth-1), 6-(10-(9H-carbazol-9-yl) anthracen-9-yl) benzofuro[2,3-b] pyridine (Benzo4-Anth-2). Chemical characterization and the structure-TADF relationship were determined using the DFT and TD-DFT techniques. The analysis of frontier molecular orbitals and molecular electrostatic potential indicated that the Benzo4-Anth-1 derivative is a good candidate for TADF due to its spatially separated donor and acceptor groups. The energy gap ΔE (S1-T2) of Cy-Anth-1, Cy-Anth-2, Benzo4-Anth-1, and Benzo4-Anth-2 is 0.0057, -0.026, 0.0528, and -0.0635 eV, respectively. While ΔE (T2-T1) for Cy-Anth-1, Cy-Anth-2, Benzo4-Anth-1, and Benzo4-Anth-2 is 0.759, 0.790, 1.019, and 0.926 eV, respectively. Donor (D = (N, N-diphenyl)) and acceptor (A = (10-(benzofuro[2,3-b] pyridin-6-yl)) in D-π-A system enhances the ΔE (S1-S0) up to 2.837 eV and decreases ΔE (S1-T2) to -0.0635 eV by making it good TADF material. Thermodynamic investigation revealed that the rise in temperature from 50–500 K, CV, CP, internal energy (U), enthalpy (H), entropy (S), and ln (Q) increases, but Gibbs free energy (G) decreases.

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Introduction

The evolution of organic light-emitting diode (OLED) technology has received a huge stride [1]. The 1st generation OLEDs [2] were based on emission produced from singlet excitons [3]. Their internal quantum efficiency (IQE) [4] was limited to 25% [5]. The 2nd generation OLEDs [6] are known as phosphorescent organic light-emitting diodes (PHOLEDs) [7], generated by organometallic phosphors [8]. These PHOLED devices use 75% triplet excitons [9], and internal quantum efficiency (IQE) is 100% [10]. Different types of thermally activated delayed fluorescent (TADF) compounds are in the market [11]. Out of them, pure organic thermally activated delayed fluorescent (TADF) gained much interest [12]. In TADF compounds, emission takes place by the intake of thermal energy and reverse intersystem crossing (RISC) [13]. If the energy gap between singlet–triplet state is small, then reverse intersystem crossing (RISC) will take place; otherwise, it will not [14]. The energy gap between S1 and T1 should be less than 100 meV [15]. Small energy gaps enable the system for reverse intersystem crossing (RISC), in which excitons jump from the T1 state to S1 thermally. Anthracene formed one of the primary fluorescent materials used for producing OLEDs. The great rigidity in its π-conjugated structure, the high-speed radiance, and the well-resolved absorption and fluorescence spectra actually demonstrate the remarkable quantum efficiency of anthracene [16]. As a consequence, anthracene derivatives are now essential to the production of many different optoelectronic devices, including photovoltaic cells, transistors, OLEDs, and fluorescence probes [17, 18]. Triplet–triplet annihilation (TTA)-based emitters can increase the efficiency of the blue TADF OLEDs. The TTA-based emitters increase the internal quantum efficiency of the device by recycling triplet excitons that would otherwise get wasted non-radiatively [19]. It has been demonstrated that anthracene derivatives can exactly match energy levels to activate the TTA pathway, which gives them promising RADF properties [20].

In this work, four anthracene derivatives were studied for thermally activated delayed fluorescence (TADF) activities. Density functional theory (DFT) calculations have been reported to describe the molecular structure and chemical characterization. This was done through the analysis of quantum chemical parameters, frontier molecular orbitals, density of states, molecular electrostatic potential, and thermodynamic parameters. By providing the IR spectrum, the functional groups and their vibrational attitudes within the studied compounds were revealed. Time-dependent density functional theory (TD-DFT) was used to investigate the absorption properties and their associated excitation spectrum analysis. Finally, the study provided a mechanism for thermally activated delayed fluorescence in order to find the thermally activated delayed fluorescence activity for each of the studied compounds.

Materials and methods

TADF mechanism

Efficient molecules satisfy the TADF conditions by having a small energy gap between singlet S1 and triplet states T1 [21]. This also minimizes the non-radiative decay by ensuring that triplet states would live long and will support reverse intersystem crossing (rISC), causing maximum fluorescence yield [22]. A small energy gap (ΔEST) is critical for reverse intersystem crossing as shown in Eq. (1).

$$K_{rIsc} = Ae^{{\left( { - \Delta E_{ST/KT} } \right)}}$$
(1)

Three different aspects are considered while calculating the energy of the lowest singlet state S1 and the lowest triplet T1 state: (1) orbital energy, i.e., energy associated with one electron for the fixed nuclear state in an excited state (2) electron repulsion energy, i.e., first-order Coulomb correction (3) exchange energy J, i.e., correction in electron–electron repulsion due to the Pauli principle, which affects the electrons in an excited state. The singlet and triplet energy gap are calculated by Eqs. (2), (3), and (4).

$$E_{S1} = E_{orb} + k + J$$
(2)
$${E}_{T1}={E}_{orb}+k-J$$
(3)
$${\Delta E}_{ST}={E}_{S1}-{E}_{T1}$$
(4)

In prompt fluorescence, there is radiative decay of electrons from singlet excited states. This phenomenon happens in nanoseconds [23]. The equilibrium between singlet and triplet excited states due to intersystem crossing kISC and reverse intersystem crossing krISC is key parameter of thermally active delayed fluorescence [24]. Excellent TADF materials are those having good yield of electrons in states singlet S1 and triplet T1 [25]. Relation between yield and equilibrium at reverse intersystem crossing is calculated by Eq. (5)

In prompt fluorescence, there is radiative decay of electrons from singlet excited states. This phenomenon happens in nanoseconds [23]. The equilibrium between singlet and triplet excited states due to intersystem crossing kISC and reverse intersystem crossing (krISC) is a key parameter of thermally active delayed fluorescence [24]. Excellent TADF materials are those having a good yield of electrons in states singlet S1 and triplet T1 [25]. The relation between yield and equilibrium at reverse intersystem crossing is calculated by Eq. (5).

$${\Phi }_{\text{rIsC}}=\frac{{K}_{rISC}}{{K}_{rISC}+{K}_{IC(triplet)}+{K}_{PH}}\approx 1$$
(5)

The condition is that krISC ≫ kPH + kIC and the energy gap between singlet and triplet states is usually small, meaning less than 0.1 eV. Total emission of thermally active delayed fluorescence can be calculated by using Eq. (6).

$${\upphi }_{F}={\upphi }_{PF}+{\upphi }_{DF}={\sum }_{i=1}^{n}{\upphi }_{PF} {\left({\upphi }_{ICS}+{\upphi }_{rISSC}\right)}^{i}={\upphi }_{PF}\frac{1}{1-{\upphi }_{ISC}{\upphi }_{rISC}}$$
(6)

\({\upphi }_{F}\) = fluorescent yield.

\({\upphi }_{PF}\) = prompt fluorescence yield.

\({\upphi }_{DF}\)= delayed fluorescence yield.

Computational methodology

Drawing and building the proposed compounds for investigation were conducted using Hyper-Chem software, as depicted in Fig. 1. The best molecular structure of the studied compounds was calculated at the DFT level of theory using the B3LYP method and the 6-311G++ basis set using the Gaussian09 package [26, 27].

Fig. 1
figure 1

Represents the structures of 9-cyano-10-diphenylamino-anthracene (Cy-Anth-1) (a)-(b), 9-(N-carbazolyl)−10-cyanoanthracene (Cy-Anth-2) (c)-(d), 10-(benzofuro[2,3-b] pyridin-6-yl)-N, N-diphenylanthracen-9-amine (Benzo4-Anth-1) (e)-(f), 6-(10-(9H-carbazol-9-yl) anthracen-9-yl) benzofuro[2,3-b] pyridine (Benzo4-Anth-2) (g), (h)

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Vibrational frequencies were obtained using the same model, while the TD-DFT approach was used to calculate the UV–vis spectrum in the gas phase. The TD-DFT technique is currently a popular and efficient method of determining the energy of the electronic excited states. Furthermore, a more accurate model for calculating spectral electronic characteristics is the Coulomb-attenuated hybrid exchange–correlation functional (CAM-B3LYP) [28]. Based on the optimized geometry, the excited state energy values, oscillator strength, and absorption spectra were obtained in the current study using CAM-B3LYP/6-311G++.

Results and discussion

Electronic excitation spectrum analysis.

Excitation spectrum analysis tells us how much energy is required for HOMO-to-LUMO molecular orbital transition [29]. The absorption calculations were executed by using TD-DFT in gas phase [30]. The energy calculations give information about excited state energies, oscillator strength, and transition of major contributing orbitals [31]. Energy calculations were done using the CAM-B3LYP functional with the 6-311G++ basic set and got UV–Visible spectra [32] by keeping the state singlet as shown in Fig. 2. It was found that Benzo4-Anth-1 shows the λ max at 483.98 nm, while Cy-Anth-2, Cy-Anth-1, and Benzo4-Anth-2 show λ max at 515.95, 539.63, and 436.94 nm, respectively. The energy gap (ΔELUMO-HOMO) of compounds Benzo4-Anth-1, Cy-Anth-2, Cy-Anth-1, and Benzo4-Anth-2 is calculated in the singlet state for thermally active delayed fluorescent materials [33] as shown in Table 1. Detailed values of the UV–Visible spectrum and population transition from HOMO to LUMO [34] are shown in Table 1.

Fig. 2
figure 2

Calculated UV–vis spectra of compounds Cy-Anth-1, Cy-Anth-2, Benzo4-Anth-1, and Benzo4-Anth-2 by the CAM-B3LYP/6-311G++ model

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Table 1 represents the excitation energy E (eV), absorption maximum λ max [35], population transition, and oscillator strength (f) values in the singlet state
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There was a need to check the phosphorescence of all compounds. Phosphorescence [36] is also calculated by keeping state triplet [37]. As the oscillator strength (f) was constant at (0.000), there was no phosphorescence, and the whole population was going back to state S1 [38]. It means all the compounds were thermally active, delayed fluorescent, not phosphorescent, as shown in Table 2.

Table 2 The excitation energy E (eV), λ max [35], population transition and oscillator strength (f) values in triplet state
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Quantum chemical parameters and HOMO & LUMO analysis

The manner in which a molecule interacts with different species can be measured by the energy associated with its frontier molecular orbitals (FMO), namely the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) [39]. The energy gap (Eg), ionization potential (IP), electron affinity (EA), electronegativity (χ), chemical hardness (η), chemical softness (S), and nucleophilicity (ω) are among those quantum parameters that are derived from HOMO and LUMO energies. The difference between HOMO and LUMO, which provides a molecule's energy gap, determines the chemical stability of molecules [40,41,42,43]. In familiar terms, higher stability is indicated by a larger energy gap, whereas higher reactivity is indicated by a smaller gap. Chemical softness indicates a molecule's ease of undergoing chemical reactions, while chemical hardness measures its resistance to these reactions. [44]. Energy reduction caused by maximum electron flow between the donor and the acceptor is measured by the electrophilicity index (ω), while the most electrophilic molecules are recognized by their nucleophilicity index. [45,46,47].

Calculations show that Benzo4-Anth-1 and Benzo4-Anth-2 have the larger energy gap, as shown in Table 3. Also, the calculated quantum chemical parameters in Table 4 show that Benzo4-Anth-1 and Benzo4-Anth-2 have high chemical stability. Large energy gap show that these compounds are thermally delayed fluorescent because they require large energy for excitation. After that, the electron will go into a metastable state and then jump into an excited state. Finally, the electron will come back to the ground state by emitting large energy in the form of fluorescence. There is maximum probability of this mechanism in Benzo4-Anth-1.

Table 3 The calculated HOMO and LUMO energies for the studied compounds, as well as the associated energy gap, using the B3LYP/6–311 G++ model
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Table 4 I.E., E.A., chemical hardness (η), chemical softness (S), ionization protentional (I.P), electrophilicity index (ω) and nucleophilicity
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The density distributions for HOMO and LUMO are essential for revealing the electrical properties of molecules by showing how charges flow through them. The HOMO denotes regions of electron donors, whereas the LUMO is for regions that have a propensity to accept electrons. The HOMO and LUMO orbital shape of all four compounds, Cy-Anth-1, Cy-Anth-2, Benzo4-Anth-1, & Benzo4-Anth-2, is shown in Fig. 3. In Benzo4-Anth-1, HOMO, there is a maximum electronic cloud on electron-donating groups like diphenylamine, while in LUMO, the whole electronic cloud is on electronegative groups like furan. Similar behavior is found in all remaining 3 compounds, Cy-Anth-2, Cy-Anth-1, and Benzo4-Anth-2, as shown in Fig. 3.

Fig. 3
figure 3

Plots for the HOMO–LUMO orbital structures of compounds Cy-Anth-1 (a), Cy-Anth-1 (b), Benzo4-Anth-1 (c), and Benzo4-Anth-2 (d)

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The structure-TADF relationship indicates that molecules having spatially separated donor and acceptor groups and a lower triplet-singlet energy level splitting can exhibit TADF. Converting triplets into singlet excitations is an essential function of a TADF emitter, and it can only be achieved if there is a minimal energy difference between the first singlet and the triplet excited state ΔEST < 0.1 eV. A prime illustration of this is the small overlap between the lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital (HOMO), which results in almost zero ΔEST. Benzyl 4-And-1 has the smallest overlap between its HOMO and LUMO orbitals, as seen in Fig. 3; therefore, it is expected to have nearly minimal ΔEST and hence the highest TADF.

Simulated IR spectrum

IR spectrum gives information about the functional groups and their vibrational attitudes in a compound. In Cy-Anth-1 Fig. 4a, the peak lies at 1620–1640 cm−1, which shows that the compound exhibits (C–H) stretching in its anthracene group [48]. The second peak lies at 1340 cm⁻1, which shows the presence of a cyano group (C≡N stretching peak) in the IR spectrum [49]. The third peak lies at 3340 cm⁻1, corresponding to C–H stretching associated with phenyl groups of diphenylamine [50] in the compound. In compound Cy-Anth-2, in Fig. 4b, the C–H stretching band attributed to the phenyl groups of the carbazole moiety is located at 3200 cm⁻1. A sharp peak lies at 1480 cm⁻1, representing C=C stretching of the benzene ring in the compound. Similarly, in compounds Benzo4-Anth-1 (Fig. 4c) and Benzo4-Anth-2 (d), there are similar functional groups like in compounds Cy-Anth-1 and Cy-Anth-2, which means there is a minor difference in their vibration amplitudes as shown in Fig. 4.

Fig. 4
figure 4

Represents the IR spectrum of compound Cy-Anth-1 (a), Cy-Anth-1 (b), Benzo4-Anth-1 (c), and Benzo4-Anth-2 (d)

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Density of state analysis

The density of state spectrum of a molecule shows the overall population analysis of orbitals in a certain energy range. The DOS spectrum is very important for calculating optical transition probability and transition rates upon absorbing or emitting light [51]. The spectrum between density of state and energy (DOS vs. E) shows HOMO has the highest contribution and LUMO has the least. The DOS spectrum for all compounds is shown in Fig. 5. From spectra it is clear that compound Benzo4-Anth-1 in Fig. 5c has a 5.52 eV energy gap between the valence band and conduction band compared to others. So maximum electron density lies in LUMO. This is a sign for maximum electron transition from the HOMO. If we analyze the Cy-Anth-2 in Fig. 5b. There is a larger energy gap between the HOMO and LUMO. In the case of Cy-Anth-1, Benzo4-Anth-2 in Figs. 5a and d, the gap between HOMO and LUMO is much larger compared to others. Their maximum electron density in HOMO lies much more below the Fermi energy level. So Benzo4-Anth-1 Fig. 5c is the best thermally activated delayed fluorescent material (TDAF).

Fig. 5
figure 5

Represents DOS spectrum of compounds Cy-Anth-1 (a), Cy-Anth-2 (b), Benzo4-Anth-1 (c), and Benzo4-Anth-2 (d)

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Thermodynamic analysis

The effect of temperature on all thermodynamic properties is calculated. The values of thermodynamic attributes of compounds were calculated in the gas phase by DFT/B3LYP/6-311G++ methods. The results generated by this calculation are listed in Tables 5, 6, 7 And 8. It was observed that the values of entropy, enthalpy, and specific heat capacity at constant volume increase and their Gibbs free energy decrease with an increase in temperature from 50 to 500 K [52]. By rise in temperature, CV, CP, internal energy (U), enthalpy (H), entropy (S), and ln(Q) increase for all four compounds while Gibbs free energy (G) decreases [53] as shown in graphs (a), (b), (c), and (d) in Fig. 6 and Tables 5, 6, 7, And 8.

Table 5 Calculated thermodynamic values by the DFT-B3LYP/6-311G++ method of the compound Cy-Anth-1
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Table 6 Calculated thermodynamic values by the DFT-B3LYP/6-311G++ method of compound Cy-Anth-2
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Table 7 Calculated thermodynamic values by the DFT-B3LYP/6-311G++ method of compound Benzo4-Anth-1
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Table 8 Calculated thermodynamic values by the DFT-B3LYP/6-311G++ method of compound Benzo4-Anth-2
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Fig. 6
figure 6

a–d represent the effect of temperature on thermodynamic properties in compounds Cy-Anth-1, Cy-Anth-2, Benzo4-Anth-1, and Benzo4-Anth-2, respectively

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Figure 6a–d represent the relation between Specific heat at constant volume (CV), specific heat at constant pressure (CP), internal energy (U), enthalpy (H), entropy (S), Gibbs free energy (G), ln (Q), and temperature (T). All the parameters increase, but Gibbs free energy decreases with a rise in temperature.

Molecular electrostatic potential analysis

The molecular electrostatic potential tells us where the maximum electronic cloud lies in a compound depending on electronegativity [54]. The red area represents maximum electronic cloud, while the blue area has minimum electronic cloud [55]. In compounds Cy-Anth-1 and Cy-Anth-2, there lies a cyano group as an auxochrome, so it is more electronegative, and there is maximum electronic cloud density. The amino groups, which are electron donating, show blue region areas as less electronic cloud. In compound Benzo4-Anth-1 and Benzo4-Anth-2, Anth-2 Fig. 7c and d, there lies a furan group, which is more electronegative. While in the blue region, there are amino groups that are electron donating. This analysis reveals that both maximum and minimum electronic clouds are distributed separately on both sides of the molecules, which is fully compatible with active TADF properties.

Fig. 7
figure 7

Represents the MEPs structures of compounds Cy-Anth-1 (a), Cy-Anth-2 (b), Benzo4-Anth-1 (c), and Benzo4-Anth-2 (d)

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Thermally activated delayed fluorescence analysis

The TADF emitters are designed in such a way as to have different spatial regions of hole and e- densities [56]. These regions are e-donating and accepting units, united in twisted conformations [57]. In thermally activated delayed fluorescence, the energy gap between excited state singlet S1 and excited triplet state T1 must be less [58], and states S1 and T1 become coupled with each other. The energy gap between S1 and T1 should be less than 100 meV [59]. A small energy gap enables the system for reverse intersystem crossing (RISC), in which excitons jump from T1 state to S1 thermally. This process is slow because fluorescence from T1 state occurs later than fluorescence from S1 state. That’s why it is called thermally activated delayed fluorescence. In compound Benzo4-Anth-1, due to the presence of furan as an electron-withdrawing and diphenyl amine as an electron-donating group, the energy gap between S1 and T2 is 0.0635 eV, while the energy gap between T2 and T1 is 0.9262 eV, as shown in Fig. 8c. As the energy gap ΔES1-T2 is less than the energy gap ΔET2-T1, it means the compound is thermally activated delayed fluorescent. Similarly, in compounds Cy-Anth-2, Cy-Anth-1, and Benzo4-Anth-2, the energy gaps (ΔES1-T2) are 0.0057, −0.0265, and 0.0528 eV, as shown in Figs. 8a, b and d, respectively. The energy gaps between ΔET2-T1 are 0.7599, 0.7906, and 1.0192 eV. In all compounds, the energy gap ΔES1-T2 is less than ΔET2-T1, meaning all compounds are thermally activated delayed fluorescent. While the Benzo4-Anth-1 compound has a minimum energy gap between ΔES1-T2 as compared to Cy-Anth-2, Cy-Anth-1, and Benzo4-Anth-2. Therefore, Benzo4-Anth-1 is the best thermally activated delayed fluorescent compared to others.

Fig. 8
figure 8

Thermally active delayed fluorescence mechanism of Cy-Anth-1 (a), Cy-Anth-2 (b), Benzo4-Anth-1 (c), and Benzo4-Anth-2 (d)

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Conclusions

Singlet and triplet spectra of experimentally synthesized compounds Cy-Anth-1, Cy-Anth-2, Benzo4-Anth-1, and Benzo4-Anth-2 are calculated. The IR spectra of the studied compounds were provided to identify their vibrational attitudes related to their functional groups. The analysis of HOMO & LUMO and MEPs revealed minimal overlap between HOMO & LUMO orbitals and maximum and minimum electronic clouds for the Benzyl 4-And-1 compound, resulting in the highest TADF. In thermodynamic analysis, it is observed by the rise in temperature that CV, CP, internal energy (U), enthalpy (H), entropy (S), and ln (Q) increase while Gibbs free energy (G) decreases for all four compounds. All compounds are found to be suitable candidates for presenting TADF, but Benzo4-Anth-1 is found to be the most TADF material compared to others. Because in Benzo4-Anth-1, due to the presence of furan as an electron-withdrawing and diphenylamine as an electron-donating group, the energy between Benzo4-Anth-1 decreases. The energy gap between S1 and T2 is −0.0635 eV, while the energy gap between T2 and T1 is 0.9262 eV.

Availability of data and materials

All the data produced in this study will be available upon request.

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Funding

This work was supported and funded by the Deanship of Scientific Research at Imam Mohammad Ibn Saud Islamic University (IMSIU) (grant number IMSIU-RP23041).

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Authors and Affiliations

  1. Department of Physics, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), 11623, Riyadh, Saudi Arabia

    Sharif Abu Alrub & Rageh K. Hussein

  2. Department of Chemistry, National Textile University, Faisalabad, 37610, Pakistan

    Yaqoob Shah

  3. Department of Chemistry, Government College University Faisalabad, Faisalabad, 38000, Pakistan

    Muhammad Umar & Asim Mansha

  4. Basic Science Department, Faculty of Technology and Education, Helwan University, Saraya El Koba, El Sawah Street, Cairo, 11281, Egypt

    Ahmed I. Ali

  5. Department of Applied Physics, Kyung Hee University, Yongin, 17104, Republic of Korea

    Ahmed I. Ali

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  1. Sharif Abu Alrub
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  4. Asim Mansha
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Contributions

Methodology, Y. S., M. U., A. M., R.K.H., and S.A.A.; software, Y. S., M. U., A. M., R.K.H., S.A.A. and A.I.A.; validation, Y. S., M. U., A. M., R.K.H., S.A.A., S.K.A. and A.I.A.; formal analysis, Y. S., M. U., A. M., R.K.H. and A.I.A.; investigation, Y. S., M. U., A. M., R.K.H.; resources, Y. S., M. U., A. M., R.K.H., S.A.A., S.K.A. and A.I.A.; data curation, Y. S., M. U., A. M., S.A.A., S.A.E., S.K.A. and A.I.A.; writing—original draft preparation, Y. S., M. U., A. M., R.K.H., S.A.A. and A.I.A.; writing—review and editing, Y. S., M. U., A. M., S.A.A., and A.I.A.; visualization, Y. S., M. U., A. M., R.K.H., S.A.A.; S.A.E., S.K.A. and A.I.A.; supervision, Y. S., M. U., A. M., R.K.H., S.A.A. and A.I.A.; project administration, Y. S., M. U., A. M., S.A.A., A.I.A. and R.K.H. All authors have read and agreed to the published version of the manuscript.

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Correspondence to Rageh K. Hussein.

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Alrub, S.A., Shah, Y., Umar, M. et al. Theoretical investigations of the auxochromic effect on novel thermally activated delayed fluorescence (TADF) anthracene derivatives. BMC Chemistry 19, 41 (2025). https://doiorg.publicaciones.saludcastillayleon.es/10.1186/s13065-025-01413-5

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BMC Chemistry

ISSN: 2661-801X

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