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Improving the open circuit voltage is a major challenge for enhancing the overall efficiency of organic solar cells. Current work has concentrated on improving open-circuit voltage by designing new molecular frameworks from an INPIC molecule having a conjugated fused core. We modulated the structure by changing the terminal groups of the reference molecule (INPIC) with seven strong electron-withdrawing units. We investigated various optoelectronic attributes, charge transfer, and photovoltaic and geometrical parameters by compiling the B3LYP/6-31G(d,p) functional of the DFT approach. The optical absorption for modulated molecules ranges from 748.51 nm to 845.96 nm while showing higher oscillation strength than INPIC. At the same time, their impressive charge transport is attributed to their smaller excitation and exciton binding energy, higher electron/hole mobility, narrower band gap, and a more than 99 % intramolecular charge transfer. The larger dipole moments help in the dense interaction of acceptors with employed donor J61 which, in turn, improves charge transfer at the donor-acceptor interface. One of the triumphs that are difficult to get in organic molecules is success in achieving a higher open circuit voltage (V OC). Our conceptualized molecular frameworks of acceptors are featured with a notable V OC improvement in the range of 1.84–2.05 eV. Thus, the results of the current investigation pave the root for architecting the acceptor molecules with impressive optoelectrical properties that may be capable of providing high photovoltaic output. Thus these acceptors can be utilized for the development of advanced organic solar cells in future. [Display omitted] • By substituting the terminal acceptor moieties of reference R, seven of INPIC were designed. • Compared to the reference molecule R, all newly designed molecules have a smaller bandgap and a higher λ max. • The lower excitation and reorganization energies of the newly formulated molecules illustrates their enhanced intramolecular charge transfer. • The V OC of all investigated molecules was calculated with respect to J61donor. [ABSTRACT FROM AUTHOR]

Kisspeptin signaling is suppressed by short term fasting. It has been reported that hypothalamic Kiss1 and Kiss1r mRNA expression decreased after 48 h of fasting in male rhesus monkey. But the mechanism involved in the reduction of kisspeptin signaling after 48 h of fasting is unknown. Recent studies have suggested the role of afferent excitatory and inhibitory pathways in the regulation of kisspeptin neurons. Therefore, this study was designed to observe the changes in the glutamate and GABA signaling during fed and 48 h fasting states by performing immunofluorescence to examine the interaction of kisspeptin neurons with NR1 subunit of NMDA receptors and by performing SYBR green qRT-PCR to measure and quantify the levels of Kiss1 , Kiss1r , NR1 and GAD67 mRNA in the POA and MBH of adult male rhesus macaque ( Macaca mulatta ) during 48 h of fasting (n = 2) and fed ad libitum (n = 2). Plasma testosterone (p < 0.05) and blood glucose levels were significantly (p < 0.001) decreased after short term fasting. Our results clearly showed that expression of hypothalamic Kiss1 , Kiss1r and NR1 mRNA was significantly (p < 0.05) reduced in adult male rhesus monkeys which were fasted for 48 h as compared to those which were fed ad libitum . There was no clear difference in the GAD67 mRNA contents between the two groups. Number of kisspeptin neurons and the interactions of kisspeptin neurons with NR1 were significantly (p < 0.05) reduced after 48 h fasting. These observations suggest that decreased kisspeptin signaling during fasting may occur due to reduction in glutamatergic inputs to kisspeptin neurons. Our results also suggest that fasting induced suppression of kisspeptin signaling is not mediated through GABAergic neurons. [ABSTRACT FROM AUTHOR]

In the current quantum chemical study, indacenodithiophene donor core-based the end-capped alterations of the reference chromophore BTR drafted eight A2-A1-D-A1-A2 type small non-fullerene acceptors. All the computational simulations were executed under MPW1PW91/6-31G (d, p) level of DFT. The UV–Vis absorption, open circuit voltage, electron affinity, ionization potential, the density of states, reorganization energy, orbital analysis, and non-covalent interactions were studied and compared with BTR. Several molecules of our modeled series BT1-BT8 have shown distinctive features that are better than those of the BTR. The open circuit voltage (V OC) of BT5 has a favorable impact, allowing it to replace BTR in the field of organic solar cells. The charge carrier motilities for proposed molecules generated extraordinary findings when matched to the reference one (BTR). Further charge transmission was confirmed by creating the complex with a PM6 donor molecule. The remarkable dipole moment contributes to the formation of non-covalent bond interactions with chloroform, resulting in superior charge mobility. Based on these findings, it can be said that every tailored molecule has the potential to surpass chromophore molecule (BTR) in OSCs. So, all tailored molecules may enhance the efficiency of photovoltaic cells due to the involvement of potent terminal electron-capturing acceptor2 moieties. Considering these obtained results, these newly presented molecules can be regarded for developing efficient solar devices in the future. [Display omitted] • Eight molecules are designed by modifying the terminal electron-rich moiety of BTR. • All molecules were processed computationally by Gaussview 6.0 and Gaussian 9.0 software. • Designed molecules outperform the reference molecule in terms of light harvesting efficiencies, electron and hole mobilities, and electronic cloud dispersion. • Proposed molecules show improved open circuit voltage and FF. • All studied molecules displayed a more favorable optoelectronic response. [ABSTRACT FROM AUTHOR]

Improving the light-harvesting efficiency and boosting open circuit voltage are crucial challenges for enhancing the efficiency of organic solar cells. This work introduces seven new molecules (SA1-SA7) to upgrade the optoelectronic and photovoltaic properties of Q-C-F molecule-based solar cells. All recently designed molecules have the same alkyl-substituted Quinoxaline core and CPDT donor but vary in the end-capped acceptor subunits. All the investigated molecules have revealed superior properties than the model (R) by having absorbance ranging from 681 nm to 782 nm in the gaseous medium while 726 nm–861 nm in chloroform solvent, with the lowest band gap ranging from 1.91 to 2.19 eV SA1 molecule demonstrated the highest λ max (861 nm) in chloroform solvent and the lowest band gap (1.91 eV). SA2 molecule has manifested highest dipole moment (4.5089 D), lower exciton binding energy in gaseous (0.33 eV) and chloroform solvent (0.47 eV), and lower charge mobility of hole (0.0077693) and electron (0.0042470). At the same time, SA7 showed the highest open circuit voltage (1.56 eV) and fill factor (0.9166) due to solid electron-pulling acceptor moieties. From these supportive outcomes, it is inferred that our computationally investigated molecules may be promising candidates to be used in advanced versions of OSCs in the upcoming period. [Display omitted] • A series of seven molecules SA1-SA7 is derived from Q-C-F molecule. • Various optoelectronic and photovoltaic properties of molecules were studied using DFT. • A narrow bandgap, low excitation energy and improved light absorption was observed in newly presented molecules. • SA7 showed significantly improved open circuit voltage and fill factor. • Results demonstrate that new molecules have potential to be used as advanced organic solar cells. [ABSTRACT FROM AUTHOR]