This article reports the reduction of the chloride [PhC(NtBu) 2 ]GeCl with potassium in THF to afford the reddish crystals of [PhC(NtBu) 2 ] 2 Ge 2 (2). The molecule of 2 contains a Ge-Ge bond. The X-ray structure and DFT calculation indicate that the Ge-Ge bond possesses an unusual gauche-bent geometry. The Ge-Ge bond length in 2 is 2.570 Å, which is very close to the single Ge-Ge interaction (2.61 Å) but significantly longer than that for typical digermenes, R 2 GeGeR 2 (2.21-2.51 Å) and the two structurally characterized digermynes (2.2850 Å and 2.2060 Å), which proves that there is no multiple bond character in 2.

Since 1988 we have analyzed 140 150 water samples from tube wells in all 19 districts of West Bengal for arsenic; 48.1% had arsenic above 10 microg/L (WHO guideline value), 23.8% above 50 microg/L (Indian Standard) and 3.3% above 300 microg/L (concentration predicting overt arsenical skin lesions). Based on arsenic concentrations we have classified West Bengal into three zones: highly affected (9 districts mainly in eastern side of Bhagirathi River), mildly affected (5 districts in northern part) and unaffected (5 districts in western part). The estimated number of tube wells in 8 of the highly affected districts is 1.3 million, and estimated population drinking arsenic contaminated water above 10 and 50 microg/L were 9.5 and 4.2 million, respectively. In West Bengal alone, 26 million people are potentially at risk from drinking arsenic-contaminated water (above 10 microg/L). Studying information for water from different depths from 107 253 tube wells, we noted that arsenic concentration decreased with increasing depth. Measured arsenic concentration in two tube wells in Kolkata for 325 and 51 days during 2002-2005, showed 15% oscillatory movement without any long-term trend. Regional variability is dependent on sub-surface geology. In the arsenic-affected flood plain of the river Ganga, the crisis is not having too little water to satisfy our needs, it is the crisis of managing the water.

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A series of organometallic compounds of group 13 metals supported by the sterically encumbered beta-diketiminate ligand containing hydrides, fluorides, chlorides, and bromide have been synthesized and structurally characterized. The synthetic strategy applied utilizes halide metathesis and reduction of metal chlorides to the corresponding hydrides. Thus, the reaction of LLi.OEt2 with MeMCl2 affords LM(Me)Cl (M = Al (1), Ga (2), In (3)) and LGaBr2 (4) with GaBr3. Reduction of LGa(Me)Cl with LiH.BEt3 leads to the formation of LGa(Me)H (10). Synthesis of LGaH(2) (12) has been accomplished by reacting LGaI2 (8) with LiH.BEt3. LAl(Me)Cl (1) and LAlH2 (6) have been converted to LAl(Me)F (5) and LAlF2 (7), respectively. The former was obtained in a reaction of LAl(Me)Cl with Me3SnF while the latter was isolated in a reaction of LAlH2 with BF3.OEt2. Similarly reaction of LGaI2 (8) with Me3SnF affords LGaF2 (9). Compounds reported herein have been characterized by elemental analyses, IR, NMR, EI-MS, and single-crystal X-ray diffraction techniques.