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Muhammad Khalid

Bio: Muhammad Khalid is an academic researcher from University of the Sciences. The author has contributed to research in topics: Molecular orbital & Natural bond orbital. The author has an hindex of 19, co-authored 156 publications receiving 991 citations. Previous affiliations of Muhammad Khalid include University of the Punjab & King Edward Medical University.


Papers
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Journal ArticleDOI
08 Sep 2020
TL;DR: Results suggest that the DA’D electron-deficient core and effective end-capped acceptors in YA1–YA4 molecules form a perfect combination for effective tuning of optoelectronic properties by lowering frontier molecular orbital (FMO) energy levels, reorganization energy, and binding energy and increasing the absorption maximum and open-circuit voltage values in selected molecules (YA1-YA4).
Abstract: This work was inspired by a previous report [Janjua, M. R. S. A. Inorg. Chem. 2012, 51, 11306–11314] in which the optoelectronic properties were improved with an acceptor bearing heteroaromatic rin...

87 citations

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TL;DR: In this article, five non-fullerene π-conjugated acceptor molecules namely BTM1, BTM2, bTM3, bamm4 and bamm5 are designed from a 16.5% efficient acceptor molecule BTP-Cl.

84 citations

Journal ArticleDOI
TL;DR: In this paper, a structural tailoring has been made at the donor and acceptor units of two recently synthesized quinoline-carbazole molecules (Q1, Q2) and two recently designed molecules Q1D1-Q1D3 and Q2D2-Q2D3 have been quantum chemically designed, respectively.
Abstract: Materials with nonlinear optical (NLO) properties have significant applications in different fields, including nuclear science, biophysics, medicine, chemical dynamics, solid physics, materials science and surface interface applications. Quinoline and carbazole, owing to their electron-deficient and electron-rich character respectively, play a role in charge transfer applications in optoelectronics. Therefore, an attempt has been made herein to explore quinoline–carbazole based novel materials with highly nonlinear optical properties. Structural tailoring has been made at the donor and acceptor units of two recently synthesized quinoline–carbazole molecules (Q1, Q2) and acceptor–donor–π–acceptor (A–D–π–A) and donor–acceptor–donor–π–acceptor (D–A–D–π–A) type novel molecules Q1D1–Q1D3 and Q2D2–Q2D3 have been quantum chemically designed, respectively. Density functional theory (DFT) and time-dependent density functional theory (TDDFT) computations are performed to process the impact of acceptor and donor units on photophysical, electronic and NLO properties of selected molecules. The λmax values (321 and 319 nm) for Q1 and Q2 in DSMO were in good agreement with the experimental values (326 and 323 nm). The largest shift in absorption maximum is displayed by Q1D2 (436 nm). The designed compounds (Q1D3–Q2D3) express absorption spectra with an increased border and with a reduced band gap compared to the parent compounds (Q1 and Q2). Natural bond orbital (NBO) investigations showed that the extended hyper conjugation and strong intramolecular interaction play significant roles in stabilising these systems. All molecules expressed significant NLO responses. A large value of βtot was elevated in Q1D2 (23 885.90 a.u.). This theoretical framework reveals the NLO response properties of novel quinoline–carbazole derivatives that can be significant for their use in advanced applications.

81 citations

Journal ArticleDOI
TL;DR: In this article, the authors performed a thorough study about different functionals and basis sets for linear and nonlinear optical properties of para-nitroanilin (PNIL) properties.
Abstract: In the present investigation, for the first time, we have performed a thorough study about different functionals and basis sets for linear and nonlinear optical (NLO) properties of para-nitroanilin...

61 citations

Journal ArticleDOI
TL;DR: In this article, a reference compound named methyl (E)-2-cyano-3-(5-(pyren-1-yl)thiophen-2-yl)-3-acrylate (MCPTR) was taken for the design of its derivatives, abbreviated from MCPTD1 to MCPTR8 compounds.
Abstract: In the present study, organic pyrene-based derivatives were selected for NLO investigation. The reference compound named methyl (E)-2-cyano-3-(5-(pyren-1-yl)thiophen-2-yl)-3-acrylate (MCPTR) was taken for the design of its derivatives, abbreviated from MCPTD1 to MCPTD8 compounds. The nonlinear optical (NLO) properties, frontier molecular orbitals (FMOs), natural bonding orbital (NBO), and UV-vis analyses of molecules (MCPTR–MCPTD8) were executed by M06 level with 6-31G(d,p) basis set. The UV-vis investigation showed that all designed compounds exhibited a redshift, and the maximum wavelength was studied in MCPTD7 (832.330 nm). The HOMO–LUMO band gaps of MCPTD1–MCPTD8 were found to be smaller as compared to those of MCPTR (3.210 eV). The global reactivity information was correlated with band gap values; MCPTD7, having a lower band gap, exhibited smaller hardness values (0.0321 Eh) with larger softness values (15.5763 Eh). The natural bond orbital analysis (NBO) helped to elucidate the hyper conjugative interactions, along with the stability and electron-transfer process. The dipole moment (μ), average polarizability 〈α〉, first hyperpolarizability (βvec) and second hyperpolarizability 〈γ〉 were computed for MCPTR–MCPTD8. Consequently, all designed compounds (MCPTD1–MCPTD8) possessed greater NLO responses than the reference compound (MCPTR). Interestingly, MCPTD7 showed a smaller energy gap and remarkable NLO response among MCPTD1–MCPTD8 compounds. The highest μtotal, 〈α〉, βvec and 〈γ〉 values for MCPTD7 were observed as 7.200, 2.40 × 10−22 esu, 2.84 × 10−27 esu and 8.6024 × 107 esu, respectively. Aptitude towards the NLO material relied upon the position of different groups, the conjugated system donor and acceptor regions. The high NLO response reveals the fact that this class of pyrene-based derivatives with a thiophene linker has remarkable contributions towards NLO technological applications.

57 citations


Cited by
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7,335 citations

Journal ArticleDOI
TL;DR: An updated summary of recent advances in the field of nanomedicines and nano based drug delivery systems through comprehensive scrutiny of the discovery and application of nanomaterials in improving both the efficacy of novel and old drugs and selective diagnosis through disease marker molecules is presented.
Abstract: Nanomedicine and nano delivery systems are a relatively new but rapidly developing science where materials in the nanoscale range are employed to serve as means of diagnostic tools or to deliver therapeutic agents to specific targeted sites in a controlled manner Nanotechnology offers multiple benefits in treating chronic human diseases by site-specific, and target-oriented delivery of precise medicines Recently, there are a number of outstanding applications of the nanomedicine (chemotherapeutic agents, biological agents, immunotherapeutic agents etc) in the treatment of various diseases The current review, presents an updated summary of recent advances in the field of nanomedicines and nano based drug delivery systems through comprehensive scrutiny of the discovery and application of nanomaterials in improving both the efficacy of novel and old drugs (eg, natural products) and selective diagnosis through disease marker molecules The opportunities and challenges of nanomedicines in drug delivery from synthetic/natural sources to their clinical applications are also discussed In addition, we have included information regarding the trends and perspectives in nanomedicine area

3,112 citations

Journal ArticleDOI
11 Oct 2012
TL;DR: It is envisioned that in the not too distant future, plant growth-promoting bacteria (PGPB) will begin to replace the use of chemicals in agriculture, horticulture, silviculture, and environmental cleanup strategies.
Abstract: The worldwide increases in both environmental damage and human population pressure have the unfortunate consequence that global food production may soon become insufficient to feed all of the world's people. It is therefore essential that agricultural productivity be significantly increased within the next few decades. To this end, agricultural practice is moving toward a more sustainable and environmentally friendly approach. This includes both the increasing use of transgenic plants and plant growth-promoting bacteria as a part of mainstream agricultural practice. Here, a number of the mechanisms utilized by plant growth-promoting bacteria are discussed and considered. It is envisioned that in the not too distant future, plant growth-promoting bacteria (PGPB) will begin to replace the use of chemicals in agriculture, horticulture, silviculture, and environmental cleanup strategies. While there may not be one simple strategy that can effectively promote the growth of all plants under all conditions, some of the strategies that are discussed already show great promise.

2,094 citations