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71.
72.
We have analyzed the unusual electronic structure of Sr2FeMoO6 combining ab initio and model Hamiltonian approaches. Our results indicate that there are strong enhancements of the intra-atomic exchange strength at the Mo site as well as the antiferromagnetic coupling strength between Fe and Mo sites. We discuss the possibility of a negative effective Coulomb correlation strength ( U(eff)) at the Mo site due to these renormalized interaction strengths. 相似文献
73.
74.
Dweltz N. E. und V. Mahadevan 《Colloid and polymer science》1962,183(1):89
Ohne Zusammenfassung 相似文献
75.
P. S. Raman und V. Mahadevan 《Colloid and polymer science》1979,257(1):110
Ohne Zusammenfassung 相似文献
76.
77.
Debapriya Gupta Ankit Kumar Gaur Pravesh Kumar Himanshu Kumar Anjali Mahadevan Dr. Sudha Devi Dr. Saonli Roy Dr. Sugumar Venkataramani 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(10):3463-3472
Light-responsive molecular systems with multiple photoswitches in C3-symmetric designs have enormous application potential. The design part of such molecular systems is critical due to its influence in several properties associated with the photoswitches. In order to tune, and in the evaluation of the design–property relationship, we synthesized 18 tripodal systems with variations in the core, linkers, connectivity, and azo(hetero)arene photoswitches. Through extensive spectroscopic and computational studies, we envisaged the factors controlling near-quantitative photoisomerization in both the directions (bistability) and the thermal stability of the metastable states. Furthermore, we also evaluated the impact of designs in obtaining reversible photo-responsive sol-gel phase transitions, solvatochromism, photo- and thermochromism. 相似文献
78.
Varghese Mathew Lizymol Xavier C. K. Mahadevan K. E. Abraham 《Journal of Thermal Analysis and Calorimetry》2011,105(1):123-127
Thermal decomposition of manganese malonate dihydrate single crystals grown by gel method has been studied using the TG-DTA
and DSC techniques. The presence of water molecules and the dehydration stages are discussed. Dielectric constant, dielectric
loss, and AC conductivity have been estimated as a function of temperature in the range of 40–120 °C for four different frequencies.
Thermal studies reveal that the material is thermally stable up to123 °C. The dielectric measurements indicate that the dielectric
parameters increase with the increase in temperature. Also, the dielectric constant and dielectric loss factor values decrease
whereas the electrical conductivities increase with the increase in frequency of the AC applied. 相似文献
79.
Stephen H. Garofalini Prof. Thiruvilla S. Mahadevan Dr. Shuangyan Xu Dr. George W. Scherer Prof. 《Chemphyschem》2008,9(14):1997-2001
Anomalously high thermal expansion is measured in water confined in nanoscale pores in amorphous silica and the molecular mechanisms are identified by molecular dynamics (MD) simulations using an accurate dissociative water potential. The experimentally measured coefficient of thermal expansion (CTE) of nanoconfined water increases as pore dimension decreases. The simulations match this behavior for water confined in 30 Å and 70 Å pores in silica. The cause of the high expansion is associated with the structure and increased CTE of a region of water ~6 Å thick adjacent to the silica. The structure of water in the first 3 Å of this interface is templated by the atomically rough silica surface, while the water in the second 3 Å just beyond the atomically rough silica surface sits in an asymmetric potential well and displays a high density, with a structure comparable to bulk water at higher pressure. 相似文献
80.
Single crystals of pure and potassium iodide (KI)-doped zinc tris-thiourea sulphate (ZTS) were grown from aqueous solutions by the slow evaporation method. The grown crystals were transparent. The lattice parameters of the grown crystals were determined by the single-crystal X-ray diffraction technique. The grown crystals were also characterized by recording the powder X-ray diffraction pattern and by identifying the diffracting planes. The FT-IR spectrum was recorded in the range 400-4500 cm−1. Second harmonic generation (SHG) was confirmed by the Kurtz powder method. The thermo gravimetric analysis (TGA) and differential thermal analysis (DTA) studies reveal that the materials have good thermal stability. Atomic absorption studies confirm the presence of dopant in ZTS crystals. The electrical measurements were made in the frequency range 102-106 Hz and in the temperature range 40-130 °C along a-, b- and c-directions of the grown crystals. The present study shows that the electrical parameters viz. dc conductivity, dielectric constant, dielectric loss factor and ac conductivity increase with increase in temperature. Activation energy values were also determined for the ac conduction process in grown crystals. The dc conductivity, dielectric constant, dielectric loss factor and ac conductivity of KI-doped ZTS crystal were found to be more than those of pure ZTS crystals. 相似文献