It is shown that the class of one-dimensional "metallic" conductors based on tetracyanoquinodimethan is not to be viewed as dominated by disorder. The experimental measurements of the electrical conductivity, magnetic susceptibility, and nuclear relaxation rates are each inconsistent with the disorder model. It is concluded that the electronic properties of these tetracyanoquinodimethan salts are primarily determined by band and interaction effects.

In this communication we report that in the quantum region of magnetic field ($\hslash {\omega }_c\gg k_{\mathrm{B}}T$) the nonparabolicity alone leads to a nonzero longitudinal magnetoresistance even if the energy and magnetic-field dependence of the relaxation time is ignored.

X-ray photoemission studies were performed on the $4d5s5p$ elements Pd through Te using monochromatized Al ($K\alpha$) radiation. With increasing atomic number the $4d$ structure evolves from $d$ bands to spin-orbit—split atomiclike core levels. Structure was observed in the $5s5p$ bands for the first time by this method. The cohesive energy was attributed to the $5p$ bands in In through Sb. Evidence for both bonding and nonbonding $5p$ bands was obtained for Te.

The shapes of the three critical lines meeting at a tricritical point are discussed in the light of the homogeneity hypothesis. We give a complete listing of possible shapes consistent with scaling. Certain possible geometries are thereby shown to be inconsistent with scaling. Application of these ideas to the crossover regions is shown to considerably simplify the "metric problem" posed by Riedel.

The $Q$-switch and polarization domain configurations in a nearly perfect Cr single crystal has been directly observed by neutron-diffraction topography in the A${\mathrm{F}}_1$ and A${\mathrm{F}}_2$ phases. The size of the domains proves to be as large as ${10}^{-3\mathrm{}}$ to ${10}^{-2\mathrm{}}$ ${\mathrm{cm}}^3$ in either phase. As far as the present observation is concerned, each domain in the A${\mathrm{F}}_2$ phase splits into domains in the A${\mathrm{F}}_1$ phase, with two possible polarizations of the transverse spin-density wave.

The statistical mechanics of a classical field theory describing mode-mode interactions is shown to lead to a theory of the Curie law and specific-heat anomaly observed in the weak itinerant ferromagnet ${\mathrm{Sc}}_3$In.

The electronic specific heat was measured for the alloys ${\mathrm{Fe}}_{49.5}{\mathrm{Rh}}_{50.5-x}{\mathrm{Ir}}_x \mathrm{}(x=1.5,3.0,5.0,6.5\mathrm{})\mathrm{}$, ${\mathrm{Fe}}_{49.1}$ ${\mathrm{Rh}}_{50.9}$, and ${\mathrm{Fe}}_{52}$${\mathrm{Rh}}_{48}$. The coefficient of the linear term, ${\gamma }_{\mathrm{AF}}$, in the specific heat of antiferromagnetic alloys was observed to contain a large magnetic contribution which is attributed to the small fraction of Fe atoms occupying Rh sites of nearly zero exchange field. The measured ${\gamma }_{\mathrm{AF}}$ values do not seem to confirm the simple electronic nature of the first-order antiferromagnetic-ferromagnetic transition assumed by the prevalent theory.

Angular distributions were measured for the (${\mathrm{O}}^{16}$, ${\mathrm{C}}^{12}$) reactions on ${\mathrm{Mg}}^{24,26}$, ${\mathrm{Al}}^{27}$, and ${\mathrm{Si}}^{28}$ at 42 MeV. States in the "$\alpha$-particle" nuclei ${\mathrm{Si}}^{28}$ and ${\mathrm{S}}^{32}$ were populated strongly for $0<~E_x<~11$ MeV, while cross sections for transitions to states in ${\mathrm{Si}}^{30}$ and ${\mathrm{P}}^{31}$ were small. The ${\mathrm{Si}}^{28}$ and ${\mathrm{S}}^{32}$ ground-state angular distributions are sharply oscillatory in nature. The 4.43-MeV state of ${\mathrm{C}}^{12}$ is strongly excited in the reaction ${\mathrm{Mg}}^{24}$(${\mathrm{O}}^{16}$, ${\mathrm{C}}^{12}$)${\mathrm{Si}}^{28}$, but not in the others.

We have studied levels in ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$ up to 10 MeV excitation energy through the ($\alpha ,{\alpha }^{\prime }$) reaction at 30 MeV and found surprising overall agreement between the observed spectra and those from $\alpha$-transfer reactions.

Using an improved one-step theory of electron shakeoff, we have performed rigorous calculations of the energy-dependent $K$-shell internal ionizaton probability. The measured probability for ${}_{}{}^{147}{}_{}{}^{}\mathrm{Pm}$ considerably exceeds the theoretical curve at low electron energies. This suggests that the direct collision process may play an important role when both a $\beta$ particle and a $K$ electron are emitted with low kinetic energies.

Single-particle energy calculations have been made for nuclei from boron through beyond lead, using a form of momentum-dependent nucleon-nucleus potential. The results are in good agreement with the observed data for energies of single-particle levels.

Experimentally measured fusion excitation functions for the reactions induced on ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$ with ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ and on ${}_{}{}^{107}{}_{}{}^{}\mathrm{Ag}$ with ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ are interpreted in terms of an equilibrium model with fission competition during de-excitation of the compound nucleus. The results of the calculation are in excellent agreement with experimental results, thereby predicting limits to angular momenta for nuclei surviving de-excitation of the compound nucleus.

The excitation function of the capture reaction ${}_{}{}^2{}_{}{}^{}\mathrm{H}{(p,\gamma )}^3\mathrm{He}$ has been measured in the range $E_p=10-17.5\mathrm{}$ MeV. An anomaly was observed and is interpreted as a broad resonance in ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ at an excitation energy of 14.5 ± 0.5 MeV with a width of about 2 MeV.

We have observed a dip at $-t\simeq 0.5$ Ge${\mathrm{V}}^2$ in $\left(\frac{{{\rho }_{00}}^{H}d\sigma }{\mathrm{dt}}\right)(\pi p\to \rho N)$ for ${\rho }^{-}$, ${\rho }^0$, and ${\rho }^{+}$ at 6 $\frac{\mathrm{GeV}}{c}$. The dominant contribution to $\left(\frac{{{\rho }_{00}}^{H}d\sigma }{\mathrm{dt}}\right)(\pi p\to \rho N)$ is from $\pi$ exchange.

We have measured the charge asymmetry in the decay $\eta \to {\pi }^{+}{\pi }^{-}\gamma$. $\eta$ mesons were produced in the reaction ${\pi }^{-}p\to \eta n$ at 730 and 810 $\frac{\mathrm{MeV}}{c}$ incident pion momentum. The asymmetry is 0.005 ± 0.006 for 36155 events. We see no evidence for $C$-invariance violation in this decay.

We have measured the charge asymmetry in the decay $\eta \to {\pi }^{+}{\pi }^{-}{\pi }^0$. $\eta \text{'}\mathrm{s}$ were produced in the reaction ${\pi }^{-}p\to \eta n$ at 730 and 810 $\frac{\mathrm{MeV}}{c}$ incident pion momentum. We obtain an asymmetry of -0.0005 ± 0.0022 for 220 659 events. We see no evidence for $C$-invariance violation in this decay.

The Padé approximant is used to calculate the higher multipole coefficients of the hydrogen-hydrogen interaction, with excellent results. However, the rate of convergence is slower and is attributed to the fact that higher excited states contribute more in the higher multipole interactions than in the dipole-dipole case.

Fine-structure transitions have been observed in the metastable $\mathrm{}\left(1s2s2p\right)\mathrm{}{}_{}{}^4{}_{}{}^{}P_J^{}{}_{}{}^{}$ state of the negative helium ion ${}_{}{}^4{}_{}{}^{}\mathrm{He}_{}^{-}{}_{}{}^{}$ using an rf resonance technique. Preliminary determinations have been made of the energy separations: $|E_{\frac{5}{2}}-E_{\frac{3}{2}}|=825.23\mathrm{}\pm 0.82$ MHz and $|E_{\frac{5}{2}}-E_{\frac{1}{2}}|=8663\mathrm{}\pm 56$ MHz. We have shown that the $J=\frac{3}{2}$ level lies between the $\frac{5}{2}$ and ½ levels. These results are to be compared with the current theoretical estimates of $E_{\frac{5}{2}}-E_{\frac{3}{2}}=-2030\mathrm{}$ MHz and $E_{\frac{5}{2}}-E_{\frac{1}{2}}=-9410\mathrm{}$ MHz.

We report a Mössbauer determination of -0.46 mm/sec for the electric-quadrupole coupling energy at the octahedral ${\mathrm{Fe}}^{3+}$ site in yttrium iron garnet. This and a recently determined value at the tetrahedral ${\mathrm{Fe}}^{3+}$ site disagree with the results of a recent linear combination of atomic orbitals-molecular orbital calculation. It is suggested that neglect of the electrostatically produced dipoles on oxygen ions may be the major cause of the disagreement. We suggest a procedure for constructing molecular orbitals taking such dipoles into account.

Fluctuations are shown to dephase an infinite cholesteric to a state in which the molecules are aligned preferentially in a plane perpendicular to a pitch axis, but in which all angles in that plane are probed with equal probability. Correlation functions in this state are calculated.