The material formula is the key to your sniplink entry. The format of material notations, which are supported by MM! search and submission functions, is described in Chapter 3. The notation should provide details of the structural unit or material in correspondance to the associated snippet.
For example, if your snippet is about alumina in general, you want to use {*Al2O3} or even shorter Al2O3, but if it is about corundum, this crystalline form should be specified by using {*Al2O3}{crphn=corundum}.
For a snippet about sapphire nanowires, {*Al2O3}{nwphn=sapphire}will be fitting.
For Ni²⁺-doped alumina nanopowder, you may want use {*Al2O3}{np}{IMc=[Ni+2]}.

Material tags are optional. They can be useful to underline the context of a sniplink. Three types of tags are possible: class tags, property tags and application tags. For each type, a maximum of three tags, separated by commata, can be given. A single tag may not exceed 32 characters.
Material class tag. A class tag classifies [sic] your material by giving a generic name or technical term. The name may relate to chemical classification, composition or structure; for example rare earth element, metal oxide or polyhalogen anion. Broad classification terms such as mineral, zeolite, or ceramic also are a good choice. Further, a tag may be role-defining, such as dopant or inclusion.
Material property tag. A material property tag should only be supplied, if it refers to a property or behavior mentioned in the snippet. For example, if the snippet refers to the thermal decomposition of the material, the tag thermal stability (or a repetition of the term thermal decomposition) makes sense. For snippet with a reference to median lethal dose, the tag acute toxicity is appropriate. Notice, that tags are supposed to relate and annotate the snippet; not the resource, the sniplink links to.
Material application tag. A material application tag hints to applications of a material. Again, the tag should derive from what information is given in the snippet. If this describes the chemical reactivity of the material, the tag catalyst may apply. Another example: the tag hydrogen storage should only be given, if the snippet content is about this subject.

A snippet is an annotation, excerpt or micro-abstract, focusing on the synthesis, properties, analysis, applications or other interesting aspects of a particular material, particle or molecular structure. The goal of a snippet is to capture a material aspect and present it as self-contained as possible. But a snippet may also be short bookmark linking to a review or other resource with information for a specific material.
The maximum length of a snippet is 768 characters. The preferred format is that of a title, note or phrased keywords. A typical snippet condenses data and facts about a material and therefore, instead of employing a narrative style, a sniplink should be composed of noun and prepositional phrases, including subordinate clauses.
The current sniplink submission procedure supports a subset of Latex-based code to edit mathematical symbols, special notations and formulae. Such code has to be based on the mathematical environment syntax employing dollar characters to enclose the special content. Some examples are given in the following.
Subscript. A single-character subscript is encoded by placing an underscore in front. Multiple characters have to be enclosed with curly braces, then preceded by an underscore. For example, H₂O as H$_2$O or LD₅₀ as LD$_{50}$.
Superscript. Like subscript encoding, but a caret is used instead of the underscore: cm³ as cm$^3$ or ²⁷Al as $^{27}$Al.
Greek letter. A greek letter is encoded via its name, preceded by a backslash: η as $\eta$ or Σ as $\Sigma$.
The dollar sign itself is encoded as \\$.

Notes are optional. Notes, if given, should relate to the material formula and/or snippet content. The maximum notes length is 512 characters. Latex-based code (see previous section) is accepted.
Notes can provide additional material identifiers or synonyms, explain used abbreviations, or comment on the snippet.
Notes should be separated by semicolon. A dictionary-type note should be entered as key/value pair; for example CAS number: 13463-67-7 or TEM: transmission electron microscopy

A sniplink is not complete without a link. Either a Document Object Identifier (DOI) or a page URL has to be provided. A large number of published journal articles today have a unique DOI number. A sniplink referring to such an article should contain the DOI. Otherwise, a URL that locates the article or a web page, on which the snippet has been based, needs to be given.