A hidden Goldstone mechanism in the Kagom\'e lattice antiferromagnet

In this paper, we study the phases of the Heisenberg model on the \kagome lattice with antiferromagnetic nearest neighbour coupling $J_1$ and ferromagnetic next neighbour coupling $J_2$. Analysing the long wavelength, low energy effective action that describes this model, we arrive at the phase diagram as a function of $\chi = \frac{J_2}{J_1}$. The interesting part of this phase diagram is that for small $\chi$, which includes $\chi =0$, there is a phase with no long range spin order and with gapless and spin zero low lying excitations. We discuss our results in the context of earlier, numerical and experimental work.Comment: 21 pages, latex file with 5 figure

Organic synthesis in water: green protocol for the synthesis of 2-amino furan derivatives

Aldehyde, dimethyl acetylenedicarboxylate (DMAD) and cyclohexyl isocyanide undergo smooth coupling in water to produce the corresponding 2-aminofuran derivatives in good yields. Water helps to avoid the use of highly toxic and environmentally unfavorable solvents for this conversion