In the present invention, a crucible formed of SiC as a main component is used as a container for a SiC solution. A metal element M (M is at least one metal element selected from at least one of a first group consisting of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho and Lu, a second group consisting of Ti, V, Cr, Mn, Fe, Co, Ni and Cu and a third group consisting of Al, Ga, Ge, Sn, Pb and Zn) is added to the SiC solution and the crucible is heated to elute Si and C, which are derived from a main component SiC of the crucible, from a high-temperature surface region of the crucible in contact with the SiC solution, into the SiC solution. In this way, precipitation of a SiC polycrystal on a surface of the crucible in contact with the SiC solution is suppressed.

In the present invention, a crucible formed of SiC as a main component is used as a container for a SiC solution. A metal element M (M is at least one metal element selected from at least one of a first group consisting of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho and Lu, a second group consisting of Ti, V, Cr, Mn, Fe, Co, Ni and Cu and a third group consisting of Al, Ga, Ge, Sn, Pb and Zn) is added to the SiC solution and the crucible is heated to elute Si and C, which are derived from a main component SiC of the crucible, from a high-temperature surface region of the crucible in contact with the SiC solution, into the SiC solution. In this way, precipitation of a SiC polycrystal on a surface of the crucible in contact with the SiC solution is suppressed.

In the present invention, a crucible formed of SiC as a main component is used as a container for a SiC solution. The SiC crucible is heated such that, for example, an isothermal line representing a temperature distribution within the crucible draws an inverted convex shape; and Si and C, which are derived from a main component SiC of the crucible, are eluted from a high-temperature surface region of the crucible in contact with the SiC solution, into the SiC solution, thereby suppressing precipitation of a SiC polycrystal on a surface of the crucible in contact with the SiC solution. To the SiC solution of this state, a SiC seed crystal is moved down from the upper portion of the crucible closer to the SiC solution and brought into contact with the SiC solution to grow a SiC single crystal on the SiC seed crystal.

In the present invention, a crucible formed of SiC as a main component is used as a container for a SiC solution. The SiC crucible is heated such that, for example, an isothermal line representing a temperature distribution within the crucible draws an inverted convex shape; and Si and C, which are derived from a main component SiC of the crucible, are eluted from a high-temperature surface region of the crucible in contact with the SiC solution, into the SiC solution, thereby suppressing precipitation of a SiC polycrystal on a surface of the crucible in contact with the SiC solution. To the SiC solution of this state, a SiC seed crystal is moved down from the upper portion of the crucible closer to the SiC solution and brought into contact with the SiC solution to grow a SiC single crystal on the SiC seed crystal.

Disclosed herein is a single nonlinear optical crystal having a chemical formula of MgIVV2, wherein IV is selected from Si, Ge, or Sn, and V is selected from P or As, wherein the single nonlinear optical crystal has a chalcopyrite and non-centrosymmetric crystal structure, with a space group of, wherein the non-centrosymmetric crystal structure is defined by unit cell parameters: a between about 5.5 to about 6 , c between about 9.5 to about 12.5 , and a unit cell volume of about 287 to about 450 .sup.3, wherein the single nonlinear optical crystal exhibits a refractive index of about 2.770 to about 2.780 and from about 2.800 to about 2.810 for no and ne respectively at a wavelength of 1,550 nm, and a nonlinear coefficient of d.sub.eff of SHG from about 80 to about 95 pm/V, wherein the single crystal MgIVV.sub.2 is substantially free of impurities.

An inorganic structure having mechanical properties that differ depending on the region in the inorganic structure, and a method for manufacturing the inorganic structure are provided. An inorganic structure (1) of the present embodiment includes a plurality of solidified portions (SA) composed of an inorganic material. The plurality of solidified portions (SA) include a first solidified portion (SA1) having a first crystallographic direction (CO1) preferentially oriented in a predetermined direction, and a second solidified portion (SA2) having a second crystallographic direction (CO2) that is a different orientation from the first crystallographic direction (CO1).

An inorganic structure having mechanical properties that differ depending on the region in the inorganic structure, and a method for manufacturing the inorganic structure are provided. An inorganic structure (1) of the present embodiment includes a plurality of solidified portions (SA) composed of an inorganic material. The plurality of solidified portions (SA) include a first solidified portion (SA1) having a first crystallographic direction (CO1) preferentially oriented in a predetermined direction, and a second solidified portion (SA2) having a second crystallographic direction (CO2) that is a different orientation from the first crystallographic direction (CO1).