Indian Institute of Technology Hyderabad (IITH) is a premier institute of science and technology established in 2008. IITH has been consistently ranked in the&nbsp;<a href="https://iith.ac.in/reports/" rel="noopener noreferrer">top 10 institutes</a>&nbsp;in India for Engineering&nbsp;<a href="https://www.nirfindia.org/2021/EngineeringRanking.html" rel="noopener noreferrer" target="_blank">according to NIRF</a>&nbsp;making it one of the most coveted schools for science and technology in the country.

IITH offers&nbsp;<a href="https://iith.ac.in/academics/under-graduate/">undergraduate programs</a>&nbsp;in all the classical engineering disciplines, applied sciences, design, as well as several modern interdisciplinary areas. Students are given a flexibility to explore a broad set of areas, and potentially pursue a minor or double major in a discipline that is not their own. Students who wish to seek a deeper understanding of their own discipline are strongly encouraged to get involved in cutting-edge research with the help of a faculty to mentor them, and earn an Honors in their own field.

The very foundation of IIT Hyderabad is based on&nbsp;<a href="https://iith.ac.in/research/">research and innovation</a>. The vibrant research culture is evident from the number of patents and publications that IITH produces consistently every year. IITH offers&nbsp;<a href="https://iith.ac.in/academics/programmes-offered/">graduate programs</a>&nbsp;at both a masters, and a doctoral level, in several diverse areas. There are separate programs for technology, design, science, and liberal arts. The&nbsp;<a href="https://iith.ac.in/academics/post-graduate/">MTech program</a>&nbsp;is offered in various modes and durations to cater to the ever-growing need of postgraduate level professionals in the country.

IITH encourages and supports&nbsp;<a href="https://iic-iith.netlify.app/index.html" rel="noopener noreferrer" target="_blank">innovation and entrepreneurship</a>&nbsp;at every stage. The minor program in entrepreneurship is open to all students of IITH, and many of the courses are offered by industrialists who are entrepreneurs themselves. There are various&nbsp;<a href="https://iith.ac.in/research/centres-incubators/">innovation centers and incubators</a>&nbsp;that promote entrepreneurship and help mentor young innovators. IITH has been very successful in building tie-ups with leading academic institutions around the globe.

IITH enjoys a very special relationship with Japanese universities and industries that goes beyond academic and research collaborations. In fact, some of the iconic buildings in IITH campus will carry the signature of Japanese architecture.

IITH creates a unique holistic ecosystem for education that offers interactive learning, a very flexible academic structure, cutting-edge research, strong industry collaboration, and entrepreneurship. This is an environment which enables students and faculty to translate their dreams into realities.

IIT Hyderabad

Alcohol complexes of 4-fluorophenylacetylene and 2-fluorophenylacetylene were investigated using IR-UV double resonance spectroscopy. Methanol forms a cyclic complex with both the fluorophenylacetylenes incorporating C-H•••O and O-H•••π hydrogen bonds, the structure of which is similar to that of the corresponding water complex but different from that of a phenylacetylene-methanol complex. The anti conformer of ethanol also binds in a similar fashion to both the fluorophenylacetylenes. Additionally, the gauche conformer of ethanol binds to 2-fluorophenylacetylene in a distinctly different structural motif that incorporates C-H•••F and O-H•••π hydrogen bonds. The OH group of trifluoroethanol interacts primarily with the π electron density of the C≡C bond. The π electron density of the C≡C bond is the principal point of interaction between the alcohols and both the fluorophenylacetylenes. The present results are indicative of the fact that fluorine substitution on the phenyl ring is sufficient to eliminate the subtle hydrogen bonding behavior of phenylacetylene. © 2011 American Chemical Society.

Department of Chemistry

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Journal of Physical Chemistry A

Interaction of alcohols with 2-fluoro- and 4-fluorophenylacetylenes: Infrared-optical double resonance spectroscopic and computational investigation

The H2O and MeOH complexes of 2-(2′-pyridyl)benzimidazole (2PBI) were investigated using laser induced fluorescence and IR-UV double resonance spectroscopic techniques. The 000 band for the S1 ← S0 electronic transition of 2PBI was observed at 31?616 cm-1, and corresponding transitions for the H2O and MeOH complexes show substantial red shifts of 1059 and 1203 cm-1, respectively. A long progression up to v′ = 5 in the 92 cm-1 vibrational mode was observed for bare 2PBI, which is considerably shortened to v′ = 2 and v′ = 1 for the H2O and MeOH complexes, respectively. The combined experimental and theoretical results suggest that both H2O and MeOH form cyclic complex with 2PBI incorporating N-H⋯O and O-H⋯ N hydrogen bonds. Comparison with other known hydrogen-bonded H2O complexes of bifunctional aza-heteroaromatic molecules suggest that 2PBI-H2O is probably one of the strongest of all known complexes. Further, the experimental data in combination with calculations suggests that the hydrogen atom/proton transfer leading to tautomeric form might be thermodynamically spontaneous in the electronic excited state, due to explicit solvent (H2O and MeOH) participation. © 2010 American Chemical Society.

Infrared-optical double resonance spectroscopic measurements on 2-(2′-Pyridyl)benzimidazole and its hydrogen bonded complexes with water and methanol

The structures of the binary complexes between phenylacetylene and several tertiary amines viz., triethylamine, 1-ethylpiperidine, 1-ethylpiperazine, 1-azabicyclo[2.2.2]octane, and 1,4-diazabicyclo[2.2.2]octane were inferred using infrared-optical double resonance spectroscopy. The IR spectra in the acetylenic C-H stretching region clearly rule out the formation of electrostatic dominated C-H⋯N hydrogen bonded complexes. The IR spectra also point to the fact that all the five tertiary amines interact with the extended π electron density of the phenylacetylene moiety, leading to the formation of multidentate C-H⋯π hydrogen bonded complexes. Additionally a very weak electrostatic C-H⋯N hydrogen bond enhances the stability of the complex marginally. The multidentate C-H⋯π hydrogen bonded complexes are stabilized by a substantial contribution from the dispersion energy. © 2010 the Owner Societies.

Fulltext

Physical Chemistry Chemical Physics

Binary complexes of tertiary amines with phenylacetylene. Dispersion wins over electrostatics

The water complexes of 4-ethynylbenzonitrile (4EBzN) were investigated with IR-UV double resonance spectroscopy. Water interacts with the π electron density of the C ≡ N group in 4EBzN, leading to the formation of a quasiplanar cyclic complex incorporating C - H⋯O and O-H⋯π hydrogen bonds. The (H2O)2 and (H2O) 3 complexes of 4EBzN are characterized by the presence of hydrogen bonding bridges between the hydrogen bond donor (aromatic C ≡ H group) and acceptor (C - N group) sites present in 4EBzN. The present structures of the water complexes are similar to the corresponding complexes of benzonitrile but are drastically different from water complexes of phenylacetylene and fluorophenylacetylenes. The infrared spectra in the O-H stretching region indicate that the stability of all the water complexes of 4EBzN is lower than that of the corresponding complexes of benzonitrile, which can be attributed to the mild electron withdrawing ability of the ethynyl group present in the para position relative to the nitrile group. Hierarchally, the C ≡ N group has the higher propensity to form hydrogen bonding relative to the acetylenic group and the benzene ring in 4EBzN. © 2010 American Chemical Society.

Hydrogen bonding to multifunctional molecules: Spectroscopic and ab initio investigation of 4-ethynylbenzonitrile-(Water)1-3 complexes

Two distinct isomers for the binary complex between phenylacetylene and methylamine were observed. The first complex is characterized by the presence of a C-H⋯N hydrogen bond between the acetylenic C-H group and the N atom of methylamine. In the second complex the N-H group of methylamine interacts with the π electron density of the benzene ring accompanied by a peripheral interaction between the methyl C-H group and the π electron density of the C≡C bond. Stabilization energies and Gibbs free energies at the complete basis set (CBS) limit of the coupled cluster theory with single, double, and perturbative triple excitations [CCSD(T)] suggest that while the C-H⋯N hydrogen bonded complex is the global minimum, the N-H⋯π hydrogen bonded complex is a high energy local minimum. The formation of the N-H⋯π complex could be related to kinetic trapping or higher accessibility. Comparison of the laser induced fluorescence (LIF) excitation and the one-color-resonant two-photon ionization (1C-R2PI) spectra suggests that formation of C-H⋯N hydrogen bonding leads to fluorescence quenching in phenylacetylene, most probably due to dipolar coupling in the excited state. The binary complex between the phenylacetylene and methylamine shows interesting isomer-dependent fluorescent properties. © 2010 American Chemical Society.

A combined spectroscopic and ab initio investigation of phenylacetylene-methylamine complex. observation of σ and π type hydrogen-bonded configurations and fluorescence quenching by weak C-H⋯N hydrogen bonding

The water complexes of 4-fluorophenylacetylene and 2-fluorophenylacetylene were investigated using IR-UV double resonance spectroscopy. Both 4-lluoro-and 2-lluorophenylacetylenes form a cyclic complex with water incorporating C-H⋯0 and O-H⋯φ hydrogen bonds. These structures are similar to the phenylacetylene-water complex, implying that the fluorine substitution on phenylacetylene does not alter the intermolecular structure. Further, the presence of fluorine enhances the interaction of water with the acetylenic π electron density. This behavior of fluorophenylacetylenes is dramatically different from that of fluorobenzene and fluorostyrene. A second water complex was also observed in the case of 2-fluorophenylacetylene in which water interacts with fluorine atom and acetylenic C-C triple bond in a double-donor fashion. Additionally, two distinct 2-fluorophenylacetylene-(water)2 complexes were also observed. The first is a cyclic complex in which two water molecules bridge the hydrogen bond donor and acceptor sites present in 2-fluorophenylacetylene. The second is a kinetically trapped higher energy structure in which one water molecule acts as a double-acceptor. © 2009 American Chemical Society.

Hydrogen bonding to multifunctional molecules: Spectroscopic and ab initio investigation of water complexes of fluorophenylacetylenes

The structure of the binary complex between phenylacetylene and borane-trimethylamine has been elucidated using IR-UV double resonance spectroscopy in combination with high level ab initio calculations at the CCSD(T) level. Borane-trimethylamine interacts primarily through multiple C-H⋯π interactions with the π electron density of the benzene ring in phenylacetylene. CCSD(T) level calculations provide reliable estimates for the interaction energy and free energy, which are in accord with the experimental observations. The DFT-SAPT calculations point out that the dispersion interaction plays a major role in the formation of the experimentally observed complex, along with a sizable contribution from electrostatics. © the Owner Societies 2009.

Infrared-optical double resonance spectroscopic measurements and high level ab initio calculations on a binary complex between phenylacetylene and borane-trimethylamine. Understanding the role of C-H⋯π interactions

The binary complexes of water with styrene and fluorostyrene were investigated using LIF and FDIR spectroscopic techniques. The difference in the shifts of S1 ← S0 electronic transitions clearly points out the disparity in the intermolecular structures of these two binary complexes. The FDIR spectra in the O-H stretching region indicate that water is a hydrogen bond donor in both complexes. The formation of a single O-H⋯π hydrogen-bonded complex with styrene and an in-plane complex with fluorostyrene was inferred based on the analysis of the FDIR spectra in combination with ab initio calculations. The in-plane complex with fluorostyrene is characterized by the presence of O-H⋯F and C-H⋯O hydrogen bonds, leading to formation of a stable six-membered ring. The synergistic effect of O-H⋯F and C-H⋯O hydrogen bonds overwhelms the O-H⋯π interaction in fluorostyrene-water complexes. © 2008 American Chemical Society.