Anti-clockwise

Stereochemistry can also be expressed in the SMILES notation [113]. Depending on the clockwise or anti-clockwise ordering of the atoms, the stereocenter is specified in the SMILES code with or respectively Figure 2-78). The atoms around this stereocenter are then assigned by the sequence of the atom symbols following the identifier or (g). This means that, reading the SMILES code from the left, the three atoms behind the identifiers ( ) or ( )( )) describe the stereochemistry of the stereocenter. The sequence of these three atoms is dependent only on the order of writing, and independent of the priorities of the atoms. 

The composite vector is seen to spiral around the z-axis and in projection moves anti-clockwise in a circle around the z-axis. The other component which is the mirror image of the first, performs a clockwise circular motion in projection along z. The decomposition into circularly polarized components can also be formulated in complex notation, Er = E0e t6. 

Consider the two-dimensional flow shown in Figure A.l. If the velocity gradient dvjdy is positive it tends to cause the element to rotate in the clockwise direction. Similarly, if dvjdx is positive it tends to cause rotation in the anti-clockwise direction. Thus, the quantity dVy/dx — dvjdy gives the net rate of rotation in the anti-clockwise direction as viewed. It is the clockwise direction about a line parallel to the 2-coordinate as viewed in the positive 2-direction. This quantity is the 2-component of the fluid s vorticity a> ... 

Molecules at a chiral centre can be labelled according to the direction in which groups of increasing molecular weight are organized around the centre rectus and sinister, abbreviated to R and S, depending on whether the direction of increment is clockwise or anti-clockwise, respectively. 

This system allows also for the indication of the absolute configuration of inherently chiral fullerenes by introducing the stereodescriptors f C) and f A) ( P = fullerene s = systematic numbering C = clockwise A = anti-clockwise). 

Thus the absolute configuration of A is R and it follows that its mirror image B must be S (the order of precedence moves anti-clockwise). 

This means that the D line of a sodium lamp (Z = 599.6 nm) was used for light, that a temperature of 25 °C was maintained and that a sample containing 1.00 g/mL of the optically active morphine, in a 1 dm tube, produced a rotation of 132° in an anti-clockwise direction. 

However, the optical activity does not tell us the actual configuration of an enantiomer. It only gives us the information whether an enantiomer rotates the plane-polarized light clockwise or anti-clockwise. 

Fig. 2.62 Structure of YbO(OH), (2, 2)HCpYb O (OH) . This is the high-pressure form of YbO(OH). The peaks of trigonal prisms are distorted anti-clockwise, and thereby the coordination number of O or (OH) by Yb becomes seven.

To introduce phase-differences, small mica plates have been used. Buerger (1951) cut small plates from the same uniform cleavage sheet, and placed one over each hole, suitably tilted to give the appropriate increase in optical path-length. Hanson, Taylor, and Lipson (1951) used mica plates to control both amplitude and phase the reciprocal lattice was represented by an array of equal holes, and placed between crossed polarizers a mica plate over each hole was rotated to some position between the two extinction positions to give the correct amplitude different signs were obtained by rotating the plate either clockwise or anti-clockwise. 

Necessarily, exactly the same set of equations can be obtained from an anti-dochvise rotation of 8 about es of the base vectors ex and es, i.e. moving the point clockwise is the same as moving the laboratory axes anti-clockwise. 

It is apparent that D(Cn) l corresponds to a clockwise rotation by —5 or an anti-clockwise rotation by 0, i.e. 

The angles are measured anti-clockwise with respect to the axis N(l)-C(4). 

In an approach of the type employed by Stevens, the metal-free corrin nucleus can be constructed, as shown in Scheme 26, by stepwise progression in either a clockwise or an anti-clockwise manner depending upon the choice, the tris-isoxazoles (294) or (295) should be accessible. 

Figure 2.16 Positive values tor an angle are generated by rotation in an anti-clockwise sense, while negative values imply clockwise rotation...

The bowl hood is lifted with tool V6, which should be screwed anti-clockwise on to the hood. 

Screw cap nut Cl anti-clockwise on the spindle and tighten with tool V13, the groove of which should be fitted over the nut wing. 

Screw on the lock ring ANTI-CLOCKWISE (left-hand thread) till the oowT hood lies TIGHTLY against the bowl body. In a new bowl, the guide marks (J will now be right in front of each other. The best way to use the spanner is to move the handle CLOCKWISE and check the motion with a heavy jerk. 

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