Wound healing activities of PVA-urea composites from Ormocarpum cochinchinense

The aim of this work is to prepare ternary blended polyvinyl alcohol (PVA)-urea hydrogels containing Ormocarpum cochinchinense, Cinnamomum zeylanicum and antibiotic cephalexin by freezing-thawing method in order to assess the wound healing qualities. In addition to being a synthetic polymer, PVA is a recyclable and biocompatible artificial polymer blend that has attracted a lot of interest in biological applications. The freezing-thawing process with PVA-urea blend is used to make hydrogel film. Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and swelling investigations were carried out for the composite membranes. Biological studies involving antibacterial, antifungal, cytotoxicity and wound healing activities were also carried out for the composite membranes. The composite membrane developed has a lot of potential for wound dressing and other applications.

Improving cardiovascular health behaviors through a comprehensive lifestyle intervention program during the pandemic in India

Funding Acknowledgements

Type of funding sources: None.

Background

We have witnessed a dramatic dip in adherence to cardiovascular health behaviors during the COVID-19 pandemic. Data from across the globe has shown that risk factors for cardiovascular disease (CVD) such as decreased physical activity, poor diet, and increased depression, loneliness, and stress have peaked during the pandemic. Having been badly affected by the pandemic and having had prolonged periods of countrywide lockdown, the at-risk and established CVD population has faced a major challenge in adhering to a healthy lifestyle in India.

Purpose

This study aimed to analyze the change in cardiovascular health behaviors brought about by a comprehensive lifestyle intervention program (CLIP) during the pandemic in India.

Methods

All at-risk and CVD patients who had participated in the CLIP from mid 2020 to mid 2022 and had completed the internally validated health behavior assessment questionnaire, pre and post-program, were included in this retrospective study. A multidisciplinary team consisting of Physician, Physiotherapist, Dietician, and Counseling Psychologist provided the sessions online and/or in-person for the home-based and hybrid programs respectively. When a combination of online and in-person sessions were provided for a subject, it was called a hybrid program. The core components of the CLIP were exercise training, education on relevant health topics, nutritional guidance and psychosocial counseling.

Results

Age of the subjects (n=50) at enrolment was 54±13 years and 40 (80%) were male. The time between pre-program and post-program assessments was 110 (IQR 47) days. Number of at-risk and CVD patients attending home-based and hybrid programs are shown in the Figure. There were 4 couples in the study cohort; 21 (50%) of the remaining 42 subjects had at least 1 other family member attend the majority of sessions. There was a significant improvement in all the cardiovascular health behaviors, namely adequate daily intake of fruits, vegetables and whole grains, choice of heart-healthy foods between meals, sufficient weekly exercise and a reduction in self-reported chronic stress, upon completion of the CLIP (Table).

Conclusions

A comprehensive lifestyle intervention program that incorporates a multipronged approach to behavior modification is effective in improving cardiovascular health behaviors in individuals at-risk as well as with established cardiovascular disease in India. The ripple effect of behavior modification in the accompanying family members needs to be studied systematically.

Efficacy of home-based versus centre-based cardiac rehabilitation in an Indian cardiovascular disease population

Funding Acknowledgements

Type of funding sources: None.

Background

Cardiac rehabilitation (CR), an integral component of cardiovascular disease (CVD) management in developed countries, is yet to become mainstream in India. With the prevailing gross mismatch between the need and the availability of CR services, an alternative model such as home-based CR may be the potential solution to challenges such as accessibility issues, transportation cost and lack of time.

Purpose

This study aimed to compare the efficacy of home-based versus centre-based CR in an Indian CVD population.

Methods

All CVD patients who participated in our centre-based and home-based CR programs between mid-2014 and mid-2022 were included in the study. Subjects who did not complete their post program evaluation (n=15) were excluded. Demographic data and data pertaining to CVD risk factors, nature of CVD, procedure undergone and details of CR program provided were documented for all subjects. A multidisciplinary team consisting of Physician, Physiotherapist, Dietician, and Counseling Psychologist provided the CR program in-person or using telehealth platforms for the centre-based and home-based programs respectively. Subjects who attended some in-person and some home-based sessions were categorized based on the nature of the majority sessions.

Results

Age of the subjects (n=106) was 60±13 years, 94 (89%) were male and 22 (21%) were residing outside Chennai. While the risk factor and disease profiles were comparable, the home-based group was younger, had more out of Chennai participants and attended more sessions over a longer duration compared to the centre-based group (Table 1). The higher number of hybrid revascularization procedures in the home-based group corroborates with this being the preferred modality for acute coronary syndrome management during the pandemic-led lockdown. There was a significant improvement in body mass index, systolic blood pressure, 6-minute walk distance and left ventricular ejection fraction in those who completed the centre-based as well as home-based CR programs (Table 2).

Conclusions

Home-based CR is as efficacious as centre-based CR, is easier to deploy and helps overcome challenges inherent to centre-based CR such as transportation and time constraints. Home-based CR has potential to become the main mode of CR delivery in low-resource settings in the future.

Identifying global status and research hotspots of heavy metal remediation: A phase upgrade study

Impact of heavy metal (HM) pollution and its understanding on environment as well as human beings has grown a lot during the last few decades. The goal of this study is to create a scientometric study on heavy metal contamination, in the period 1989 to 2020, in order to provide futuristic goals for the new researchers on wastewater treatment. For this, a search was conducted in the Web of Science (WoS) and Scopus databases, related to heavy metal pollution. Totally, 37,154 records were collected during the study period from 1989 to 2020. The findings revealed that China, the United States, and India has most referenced papers across a wide range of trans disciplinary issues such as toxicity, technology, and pollution. As a result, this study concludes that more research on various treatment methods is required in order to obtain high-quality water for consumption and routine activities, with the incorporation of various treatment tasks poses various challenges for the upcoming future studies.

Evaluation of global research trends in photocatalytic degradation of dye effluents using scientometrics analysis

Photocatalysis technology is observed to be an effective approach for its outstanding performance to eliminate wide range of organic pollutants including dyes in textile effluent. Despite growing number of studies, there is no scientometric perspective addressing the research topic "photocatalytic degradation of dye effluents". In this regard, a total of 954 documents were extracted from the Web of Science (WoS) database using keywords search to cover all the published documents during the period 1996-2020. Publications in this area started to increase exponentially from year 2007. The most dominant subject categories were Engineering, Chemistry and Environmental Science & Ecology. Applied Catalysis B-Environmental and Desalination & Water Treatment were identified as the most-impactful and productive journals respectively. Authors based in India accounted for 29.6% of total publications followed by China (14.2%); but in terms of citations Spain and Italy were more influential. Based on keyword analysis, azo dyes, TiO2, nanoparticles, adsorption, methylene blue, visible light, ZnO and kinetics are the most studied, and visible light mediated photocatalysis, hybrid treatment systems, nano based photocatalysis and more recently, metal based photocatalysis, have received most attention. Studies on cost and energy analysis, recovery of value-added products, development of more efficient photocatalytic materials and new photocatalyst regeneration approaches should be considered for future research. This study therefore, provides a comprehensive understanding about the trends and patterns of the specified research field worldwide.

Identification of Stable and Multiple Environment Interaction QTLs and Candidate Genes for Fiber Productive Traits Under Irrigated and Water Stress Conditions Using Intraspecific RILs of Gossypium hirsutum var. MCU5 X TCH1218

Cotton productivity under water-stressed conditions is controlled by multiple quantitative trait loci (QTL). Enhancement of these productivity traits under water deficit stress is crucial for the genetic improvement of upland cotton, Gossypium hirsutum. In the present study, we constructed a genetic map with 504 single nucleotide polymorphisms (SNPs) covering a total span length of 4,416 cM with an average inter-marker distance of 8.76 cM. A total of 181 intra-specific recombinant inbred lines (RILs) were derived from a cross between G. hirsutum var. MCU5 and TCH1218 were used. Although 2,457 polymorphic SNPs were detected between the parents using the CottonSNP50K assay, only 504 SNPs were found to be useful for the construction of the genetic map. In the SNP genotyping, a large number of SNPs showed either >20% missing data, duplication, or segregation distortion. However, the mapped SNPs of this study showed collinearity with the physical map of the reference genome (G. hirsutum var.TM-1), indicating that there was no chromosomal rearrangement within the studied mapping population. RILs were evaluated under multi-environments and seasons for which the phenotypic data were acquired. A total of 53 QTL controlling plant height (PH), number of sympodial branches, boll number (BN), and boll weight (BW) were dissected by QTL analysis under irrigated and water stress conditions. Additionally, it was found that nine QTL hot spots not only co-localized for more than one investigated trait but were also stable with major QTL, i.e., with > 10% of phenotypic variation. One QTL hotspot on chromosome 22 flanked by AX-182254626-AX-182264770 with a span length of 89.4 cM co-localized with seven major and stable QTL linked to a number of sympodial branches both under irrigated and water stress conditions. In addition, putative candidate genes associated with water stress in the QTL hotspots were identified. Besides, few QTL from the hotspots were previously reported across various genetic architects in cotton validating the potential applications of these identified QTL for cotton breeding and improvement. Thus, the major and stable QTL identified in the present study would improve the cotton productivity under water-limited environments through marker-assisted selection.

Education-based Self-management Intervention on Awareness among Patients with Systemic Lupus Erythematosus at Tertiary Care Hospital, Chennai, India

Introduction: Education-based self-management intervention that incorporates both social support and health education have reduced pain, improved function and delayed disability among patients with lupus. Aim: To assess the effect of education-based self-management intervention on awareness among patients with Systemic Lupus Erythematosus (SLE) at tertiary care hospital. Materials and Methods: The quantitative experimental study one group pretest post-test design using purposive sampling technique was conducted on 55 patients, who were all diagnosed with SLE in Rheumatology Outpatient Department, Tertiary Care Hospital, Chennai, Tamil Nadu, India. The patients received the intervention “education-based self-management” which comprised of audio recorded powerpoint teaching on various aspects of SLE like definition, risk factors, signs and symptoms diagnostic investigations, treatment, complications and self-care measures. The investigator taught a group of 4-5 patients for 30-40 minutes using the presentation, followed by which they were provided a booklet on self-management guidelines. The pre and post-test self-management awareness determined through reliable and valid self-structured questionnaire (SLE awareness questionnaire) and their values were analysed through inferential and descriptive statistics. Results: The SLE was reported to be highest among the age group of 21-35 years (72.7%), with higher incidence in females 96.4% than male 3.6%. Majority (n=44) 80% of the patients were founds to have inadequate level of awareness in the pretest. During the post-test on 15th and 30th day, the awareness among the patients was found to be adequate with the score of 38.2% and 94.5%, respectively. There was a significant difference noted in level of awareness between pretest and post-test on 15th day at p-value=0.04 and between pretest and post-test on 30th day at p-value=0.01. Conclusion: The education-based self-management intervention is effective in improving the awareness levels among patients with SLE and it can also be effective for patients to manage their symptoms.

Similar biologics in India: A story of access or potential for compromise?

Biosimilars or similar biotherapeutic products are the biological products approved by regulatory agencies based on the demonstration of similarity in quality, safety and efficacy with reference biologics (or original biologics). Though biosimilars could be considered as interchangeable therapeutic alternatives over original biologics, there are concerns regarding their similarity in effectiveness and safety with reference product along with the level of evidence of similarity required for approval. The biosimilars, particularly, monoclonal antibodies that are developed based on the complex manufacturing processes, require stringent comparative evaluations. The Indian Regulatory Authorities in July 2012 developed the first guidelines for approval of similar biologics, which comprised requirements for the manufacturing process, quality evaluation, preclinical and clinical studies, as well as post-marketing studies. The 2016 guidelines, an update to previous guidelines, were released with the intent to provide a well-defined pathway at par with international regulations for the approval of similar biologics in India. This article highlights the key attributes of the 2016 Regulatory Guidelines and also describes the aspects such as interchangeability, nomenclature and labelling of similar biologics in India. Rigorous consideration is imperative for highly complex similar biologics of monoclonal antibodies on a case-to-case basis.

Outcome of Experienced Based Learning (Field Trip) As a Learning Technique in Gaining Knowledge among Graduate and Post Graduate Nursing Students

Education brings changes in behavior of the individual in a desirable manner. It aims at all round development of an individual to become mature, self-sufficient, intellectually, culturally refined, socially efficient and spiritually advanced. In experience- based is that the experience of the learner occupies central place in all considerations of teaching and learning. A key element of experience-based learning is that learners analyze their experience by reflecting, evaluating and reconstructing it in order to draw meaning from it in the light of prior experience. The main aim of the study is to assess the knowledge of nursing students before and after Experience based learning and to determine the attitude of EBL at the end of the field trips. A quasi Experimental research design was adopted. Sample free technique was used to select the 90 B.sc and M.sc (N) students. The data was collected by using semi structured knowledge questionnaire. Inferential and descriptive statistics was used to analyze the data. There was a significant difference in pre test and post test mean score (t= 15.98 at p<0.001). A weak positive correlation was found between post- test knowledge and attitude. There is a significant improvement in knowledge of students in various child welfare services among the present students (c =3.18±.421) than the previous year (c=2.86 ±.371).

Physicochemical properties and radiolytic degradation studies on tri-iso-amyl phosphate (TiAP)

The solvent composed of tri-iso-amyl phosphate (TiAP) in n-dodecane (n-DD) is regarded as a promising candidate for reprocessing of spent fuel. In this context, the radiolytic degradation of a solution of TiAP in n-dodecane was investigated by irradiating the solvent to various absorbed dose levels of γ-radiation. The neat extractant or a solution of extractant in n-dodecane was irradiated in the presence of nitric acid. Physicochemical properties such as density, viscosity and interfacial tension (IFT) were measured for unirradiated and irradiated solutions. The extent of degradation was determined by measuring the variation in extraction behavior of U(VI) and Pu(IV) with irradiated solvent systems. Uranium and plutonium retention with irradiated solvents was also measured. The distribution ratio of uranium and plutonium increased with increase in absorbed dose. Effect of alpha degradation was studied by plutonium retention as a function of time using 1.1 M TiAP/n-DD. Laser desorption/ionization mass spectrometric technique was employed to identify the possible radiolytic degradation products. Similar studies were also carried out with tri-n-butyl phosphate (TBP) based solvent system under identical experimental conditions and the results are compared.

Improvement in treatment of soak liquor by combining electro-oxidation and biodegradation

A combined process involving electro-oxidation and biodegradation by halophilic bacteria was applied to treat wastewater effectively for discharge.

Demonstration of trivalent actinide partitioning from simulated high-level liquid waste using modifier-free unsymmetrical diglycolamide in n-dodecane

Partitioning of trivalent americium from fast-reactor (FR) simulated high-level liquid waste (SHLLW) has been demonstrated, for the first time, using a modifier-free organic phase containing an unsymmetrical diglycolamide, N,N,-didodecyl-N′,N′-dioctyl-3-oxapentane-1,5-diamide (D3DODGA), in n-dodecane (n-DD). The extraction behavior of various metal ions present in the FR-SHLLW that contained about 3.2 g/L of trivalent metal ions (Am(III) and Ln(III)) was studied using a solution of 0.1 M D3DODGA/n-DD, by batch equilibration mode. The extraction of Am(III) was accompanied by the co-extraction of all lanthanides and unwanted metal ions such as Zr(IV), Y(III), and Pd(II) from FR-SHLLW. The co-extraction of unwanted metal ions was minimized by adding a suitable aqueous soluble complexing agents to FR-SHLLW, prior to extraction. As a result, trans-1,2-diaminocyclohexane-N,N,N′N′-tetraacetic acid (CyDTA) was identified as an appropriate reagent for preventing the extraction of zirconium and palladium, that posed problems during recovery of trivalent metal ions from the loaded organic phase. The stripping of behavior of Am(III) and Ln(III) from the loaded organic phase was studied using dilute nitric acid in batch equilibration mode. Based on those results, a counter-current mixer-settler run was performed in a 20-stage mixer-settler. About 99.9% of Am(III), Ln(III) and Y(III) from FR-SHLLW in 0.1 M D3DODGA/n-DD was achieved in 20 contacts and the recovery of Am(III) and other trivalents from the loaded organic phase was achieved in 5 contacts using 0.01 M nitric acid. The study demonstrated the possibility of using the modifier-free reagent, D3DODGA, for the separation of trivalent actinides from FR-SHLLW.

Studies on the feasibility of using completely incinerable reagents for the single-cycle separation of americium(III) from simulated high-level liquid waste

The extraction and stripping behavior of various metal ions present in the fast reactor simulated high-level liquid waste (FR-SHLLW) was studied using a solvent phase composed of a neutral extractant, N,N,-didodecyl-N′,N′-dioctyl-3-oxapentane-1,5-diamide (D3DODGA) and an acidic extractant, di-2-ethylhexyl diglycolamic acid (HDEHDGA) in n-dodecane (n-DD). The third phase formation behavior of the solvent formulation D3DODGA + HDEHDGA/n-DD, was studied when it was contacted with FR-SHLLW, and the concentration of neutral and acidic extractant needed to avoid the third phase formation was optimized. The distribution ratio of various metal ions present in FR-SHLLW was measured in a solution of 0.1 M D3DODGA + 0.2 M HDEHDGA/n-DD. The extraction of Am(III) was accompanied by the co-extraction of lanthanides and unwanted metal ions such as Zr(IV), Y(III), and Pd(II). A procedure was developed to minimize the extraction of unwanted metal ions by using aqueous soluble complexing agents in FR-SHLLW. Based on those results, the counter-current mixer-settler run was performed in a 20-stage mixer-settler. Quantitative extraction of Am(III), Ln(III), Y(III), and Sr(II) in 0.1 M D3DODGA + 0.2 M HDEHDGA/n-DD was observed. The recovery of Am(III) from the loaded organic phase was carried out by the optimized aqueous formulation composed of 0.01 M diethylenetriaminepentaacetic acid (DTPA) + 0.5 M citric acid (CA) at pH 1.5. The stripping of Am(III) was accompanied by co-stripping of some early lanthanides. However the later lanthanides (Eu(III) and beyond) were not back extracted to Am(III) product. Therefore, the studies foresee the possibility of intra-lanthanides as well as lanthanide-actinide separation in a single-processing cycle.

Thermal and magnetic properties and vibrational analysis of 4-(dimethylamino) pyridine: a quantum chemical approach

The FT-IR and FT-Raman spectra of 4-(dimethylamino) pyridine (4DMAP) have been recorded in the region 4000-500 cm(-1)and 3500-100 cm(-1). Quantum chemical calculations of energy, geometry and vibrational wavenumbers of 4DMAP were carried out by using ab initio HF and density functional theory (DFT/B3LYP) with complete relaxation in the potential energy surface using 6-311++G(d,p) basis set. The harmonic vibrational wavenumbers were calculated and the scaled wavenumbers have been compared with the experimental FT-IR and FT-Raman spectra. The quantum chemical parameters have been computed from the HOMO-LUMO energy values. Temperature dependence thermodynamic parameters and magnetic properties of the title compound have been analyzed. Using NBO analysis the stability of the molecule arising from hyper-conjugative interactions, charge delocalization has been analyzed. The first-order hyper-polarizability (β) values of the title molecule were computed by B3LYP method. Finally the theoretically spectrograms for FT-IR and FT-Raman spectra of the title molecule have been constructed which show good agreement with recorded spectra.

Effect of Tribulus terrestris on Haloperidol-induced Catalepsy in Mice

Haloperidol, an antipsychotic drug, leads to the development of a behavioural state called catalepsy, in which the animal is not able to correct an externally imposed posture. In the present study we have attempted to evaluate the anticataleptic effect of Tribulus terrestris on haloperidol-induced catalepsy in albino mice. Mice were allocated to four groups, each group containing six animals. Both, the test drug, Tribulus terrestris and the standard drug trihexyphenidyl were uniformly suspended in 1% gum acacia solution. Catalepsy was induced in mice with haloperidol (1.0 mg/kg, intraperitoneally). The first group received the vehicle (10 ml/kg, orally), the second group received trihexyphenidyl (10 mg/kg, orally) and the remaining two groups received Tribulus terrestris (100, 200 mg/kg, orally). The animals were assessed after single and repeated dose administration for ten days, 30 min prior to haloperidol, using standard bar test. The result of the present study demonstrates Tribulus terrestris has a protective effect against haloperidol-induced catalepsy, which is comparable to the standard drug used for the same purpose. Our study indicates Tribulus terrestris can be used to prevent haloperidol-induced extrapyramidal side effects.

Theoretical investigations on the molecular structure, vibrational spectra, thermodynamics, HOMO-LUMO, NBO analyses and paramagnetic susceptibility properties of p-(p-hydroxyphenoxy)benzoic acid

The experimental FT-IR (4000-400 cm(-1)) and FT-Raman (3500-100 cm(-1)) spectra of p-(p-hydroxyphenoxy) benzoic acid have been recorded. Quantum chemical calculations of energies, geometries, and vibrational wavenumbers of p-(p-hydroxyphenoxy) benzoic acid (PPHPBA) are carried out using HF and DFT/B3LYP methods with 6-311G (d,p) basis set. The optimized geometrical parameters obtained by B3LYP method show a good agreement with experimental data. The difference between the observed and scaled wave number values of most of the fundamentals is very small. The complete assignments were performed on the basis of the potential energy distribution (PED) of the vibrational modes calculated with scaled quantum mechanical method. The calculated HOMO and LUMO energies allow the calculation of atomic and molecular properties and they also show that charge transfer occurs in the molecule. A detailed molecular picture of PPHPBA and its intermolecular interactions were obtained from NBO analysis. The temperature dependence of various thermodynamic parameters was also studied. The paramagnetic behavior of the molecule under consideration has been investigated and the variation of paramagnetic susceptibility with temperature has been studied.

Vibrational spectra, NBO analysis, first order hyperpolarizabilities, thermodynamic functions and NMR chemical shielding anisotropy (CSA) parameters of 5-nitro-2-furoic acid by ab initio HF and DFT calculations

In this work, FT-IR and FT-Raman spectra are recorded on the solid phase of 5-nitro-2-furoic acid (abbreviated as NFA) in the regions 4000-400 cm(-1) and 3500-100 cm(-1) respectively. The geometrical parameters, vibrational assignments, HOMO-LUMO energies and NBO calculations are obtained for the monomer and dimer of NFA from HF and DFT (B3LYP) with 6-311++G (d, p) basis set calculations. Second order perturbation energies and electron density (ED) transfer from filled lone pairs of Lewis base to unfilled Lewis acid sites of NFA are discussed on the basis of NBO analysis. Intermolecular hydrogen bonds exist through COOH groups; give the evidence for the formation of dimer entities in the title molecule. The theoretically calculated harmonic frequencies are scaled by common scale factor. The observed and the calculated frequencies are found to be in good agreement. The thermodynamic functions were obtained for the range of temperature 100-1000 K. The polarizability, first hyperpolarizability, anisotropy polarizability invariant has been computed using quantum chemical calculations. The chemical parameters were calculated from the HOMO and LUMO values. The NMR chemical shielding anisotropy (CSA) parameters were also computed for the title molecule.

Vibrational spectral analysis, computation of thermodynamic functions for various temperatures and NBO analysis of 2,3,4,5-tetrachlorophenol using ab initio HF and DFT calculations

FT-IR and FT-Raman spectra of 2,3,4,5-tetrachlorophenol (TCP) have been recorded in the regions 4000-400 cm(-1) and 3500-100 cm(-1) respectively. The total energy calculations of TCP were tried for the possible conformers. The molecular structure, geometry optimization, vibrational frequencies were obtained by the ab initio and DFT levels of theory (B3LYP and B3PW91) with the standard basis sets, 6-311++G(d, p) and 6-311+G(d, p) for C1 and C2 conformers. The harmonic frequencies were calculated and the scaled values were compared with experimental FT-IR and FT-Raman spectra. The observed and the calculated frequencies are found to be in good agreement. Stability of the molecule arising from hyper conjugative interactions, charge delocalization has been analyzed using natural bond orbital (NBO) analysis. The thermodynamic functions (heat capacity, entropy, vibrational partition function and Gibbs energy) from spectroscopic data by statistical methods were obtained for the range of temperature 100-1000 K. The polarizability, first hyperpolarizability, anisotropy polarizability invariant has been computed using quantum chemical calculations. The chemical parameters were calculated from the HOMO and LUMO values.

Rotational isomers, density functional theory, vibrational spectroscopic studies, thermodynamic functions, NBO and HOMO-LUMO analyses of 2,6-Bis(chloromethyl)pyridine

The FT-IR and FT-Raman spectra of 2,6-Bis(chloromethyl)pyridine (BCMP) have been recorded in the regions 4000-400 cm(-1) and 3500-100 cm(-1), respectively. The total energy calculations of BCMP were tried for the possible rotational isomers. The molecular structure, geometry optimization, vibrational frequencies were obtained by the HF and density functional theory (DFT/B3LYP) method with 6-311+G(d,p) basis set for the most stable rotational isomer "R3". The harmonic frequencies were calculated and the scaled values were compared with experimental FT-IR and FT-Raman spectra. The observed and the calculated frequencies are found to be in good agreement. The calculated HOMO and LUMO energies show that charge transfer occurs in the molecule. The stability of the molecule was analyzed using NBO analysis. The thermodynamic functions (heat capacity, entropy, vibrational partition function and Gibbs energy) were obtained for the range of temperature 100 K-700 K.

Density functional theory, comparative vibrational spectroscopic studies, NBO, HOMO-LUMO analyses and thermodynamic functions of N-(bromomethyl)phthalimide and N-(chloromethyl)phthalimide

Quantum mechanical calculations of energies, geometries, and vibrational wavenumbers of N-(bromomethyl)phthalimide and N-(chloromethyl)phthalimide are carried out using density functional theory (DFT/B3LYP) method with 6-31G and 6-311G(d,p) basis sets. The optimized geometrical parameters obtained by B3LYP method show good agreement with experimental data. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. A detailed interpretation of the infrared and Raman spectra of N-(bromomethyl)phthalimide and N-(chloromethyl)phthalimide was also reported. The calculated HOMO and LUMO energies show that charge transfer occurs in the molecules. The thermodynamic functions of N-(bromomethyl)phthalimide and N-(chloromethyl)phthalimide have been performed at B3LYP/6-31G and B3LYP/6-311G(d,p) basis sets. The theoretical spectrograms for FT-IR and FT-Raman spectra of N-(bromomethyl)phthalimide and N-(chloromethyl)phthalimide have also been constructed.

Trimethyl-ammonium 2,6-dioxo-5-(2,4,6-trinitro-phen-yl)-1,2,3,6-tetra-hydro-pyrimidin-4-olate

In the title barbiturate salt (trivial name: trimethyl­ammonium 2,4,6-trinitro­phenyl­barbiturate), C₃H₁₀N⁺·C₁₀H₄N₅O₉⁻, the asymmetric unit contains two sets of anion–cation moieties. The dihedral angle between the rings in the anions are 44.0 (3) and 45.7 (3)°. Adjacent anions are connected into ribbons along [100] through R₂²(8) ring motifs formed by N—H⋯O hydrogen bonds involving the barbiturate rings. Attached to both sides of these ribbons via N—H⋯O hydrogen bonds are the trimethyl­ammonium cations. C—H⋯O hydrogen bonds are also observed.

Methyl 2,2-bis-(2,4-dinitro-phen-yl)ethano-ate

In the title compound, C(15)H(10)N(4)O(10), the dihedral angle between the aromatic rings is 89.05 (16)°. One O atom of one of the nitro groups is disordered over two sites in a 0.70:0.30 ratio. In the crystal, the mol-ecules are linked by weak C-H⋯O inter-actions.