Host-guest and network structures of some tetraphenylmethane derivatives

Dinitro and tetracyano derivatives of tetraphenylmethane (TPM) are identified as new host materials that include THF, water and MeCN. The crystal structures of the host-guest complexes are reminiscent to those of the related host compound tetranitrotetraphenylmethane (TNTPM) studied by us previously. Guest loss has been measured quantitatively. The crystal structures are characterized by O-H…O, C-H…O, C-H…N and C-H…∏ interactions. It is interesting to note that while the unsubstituted TPM and some of its other derivatives form guest-free crystals, the nitro and cyano derivatives form more open structures

Norfloxacin sesquihydrate

In the crystal structure of the title compound [systematic name: 1-ethyl-6-fluoro-4-oxo-7-(piperazin-4-ium-1-yl)-1,4-dihydro­quinoline-3-carboxyl­ate sesquihydrate], C16H18FN3O3·1.42H2O, N—H⋯O and O—H⋯O hydrogen bonds assemble the mol­ecules in a two-dimensional layered corrugated sheet structure parallel to the b axis. The water mol­ecules are disordered [occupancies 0.741 (11) and 0.259 (11)]

Structural basis for bending of organic crystals

Bending is observed in organic crystals when the packing is anisotropic in such a way that strong and weak interaction patterns occur in nearly perpendicular directions

4-(3-Carb­oxy-1-ethyl-6-fluoro-4-oxo-1,4-dihydroquinolin-7-yl)piperazin-1-ium 4-carb­oxy­benzoate–benzene-1,4-dicarb­oxy­lic acid (2/1)

In the title compound, C16H19FN3O3 +·C8H5O4 −·0.5C8H6O4, the benzene-1,4-dicarb­oxy­lic acid mol­ecule is located on a centre of symmetry. In the crystal, the mol­ecules and ions are connected by inter­molecular C—H⋯O and O—H⋯O hydrogen bonds and π–π stacking inter­actions [with a centroid–centroid distance of 3.402 (2) Å], generating a three-dimensional supra­molecular structure

Ultra high speed full adder for biomedical applications

In the field of biomedical engineering high performance CPU for digital signal processing plays a significant role. Frequency efficient circuit is a paramount requirement for the portable digital devices employing various digital processors. In this work a novel high speed one-bit 10T full adder with complemented output was described. The circuit was constructed with XOR gates which were built using two CMOS transistors. The XOR gate was constructed using 2T multiplexer circuit style. It was observed that power consumption of the designed circuit at 180nm with supply voltage 1.8V is 183.6 uW and delay was 1.809 ps whereas power consumption at 90nm with supply voltage 1.2V is 25.74 uW and delay was 8.245 ps. The observed Power Delay Product (PDP) in 180nm (at supply voltage 1.8V) is 0.33 and in 90nm (at supply voltage 1.2V) is 0.212. The work was extended by implementing a 32-bit Ripple Carry Adder (RCA) and was found that the delay at 180nm is 93.7ps and at 90nm is 198ps. The results were drawn at 180nm and also 90nm technology using CAD tool. The results say that the present work offered significant enhancement in speed and PDP compared with existing designs

Sorting of polymorphs based on mechanical properties. Trimorphs of 6-chloro-2,4-dinitroaniline

Mechanical shearing of crystals of a polymorph with a layered structure may be used to separate them from harder crystals of a visually indistinguishable polymorph that resist such shearing

Three-component carboxylic acid-bipyridine lattice inclusion host. Supramolecular synthesis of ternary cocrystals

Cocrystallization of 1,3,5-cyclohexanetricarboxylic acid with 4,4'-bipyridine bases of different CH2 chain lengths (n = 0, 2, 4) has afforded the ternary host framework [H3CTA·bipy-eta(gauche)·(bipy-bu)0.5] (2), sustained by O-H···N hydrogen bonds. Inclusion of p-dichlorobenzene in the square voids of host 2 provides the first example of a quaternary cocrystal. Crystal structures of ternary cocrystals 1-3 show that methylene chains of bipy bases are not mere inert spacer units but have a conformational and structural role in controlling the supramolecular architecture of molecular complexes with carboxylic acids