pattern - What is a Russian Word™?

_{In the spirit of the What is a Word™/Phrase™ series started by JLee, a special brand of Phrase™ and Word™ puzzles.}

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If a word conforms to a special rule, I call it a Russian Word™.
Use the examples below to find the rule.

$$ % set Title text. (spaces around the text ARE important; do not remove.) % increase Pad value only if your entries are longer than the title bar. % \def\Pad{\P{1.0}} \def\Title{\textbf{ Russian }} % \def\S#1#2{\Space{#1}{20px}{#2px}}\def\P#1{\V{#1em}}\ \def\V#1{\S{#1}{9}} \def\T{\Title\textbf{Words}^{\;\!™}\Pad}\def\NT{\Pad\textbf{Not}\T\ }\displaystyle \smash{\lower{29px}\bbox[yellow]{\phantom{\rlap{rubio.2018.03.05}\S{6px}{0} \begin{array}{cc}\Pad\T&\NT\\\end{array}}}}\atop\def\V#1{\S{#1}{5}} \begin{array}{|c|c|}\hline\Pad\T&\NT\\\hline % \text{MOTHER}&\text{SISTER}\\ \hline \text{GENETICS}&\text{CELL}\\ \hline \text{ERRAND}&\text{CREDIT}\\ \hline \text{INACCURATE}&\text{UNTRUE}\\ \hline \text{HELICOPTER}&\text{ROTORCRAFT}\\ \hline \text{POLICE}&\text{ARMY}\\ \hline \text{CAGE}&\text{BIRD}\\ \hline \text{NANOSECOND}&\text{MILISECOND}\\ \hline \text{HEALER}&\text{DOCTOR}\\ \hline \text{PRINCE}&\text{PURPLE}\\ \hline \text{CUBISM}&\text{PAINTING}\\ \hline \text{SEASHORE}&\text{SUNSET}\\ \hline \text{BANANA}&\text{STRAWBERRY}\\ \hline \hline \end{array}$$

Or, in a CSV:

RUSSIAN Words™,Not RUSSIAN Words™
MOTHER, SISTER
GENETICS, CELL
ERRAND, CREDIT
INACCURATE, UNTRUE
HELICOPTER, ROTORCRAFT
POLICE, ARMY
CAGE, BIRD

NANOSECOND, MILISECOND
HEALER, DOCTOR
PRINCE, PURPLE
CUBISM, PAINTING
SEASHORE, SUNSET
BANANA, STRAWBERRY

These are not the only examples of Russian Words™, many more exist.

What makes a word Russian?

Answer

A Russian Word™

Can be decomposed into pairs of letters, each which is a chemical element symbol. For instance, MOTHER = Mo Th Er, or Molybdenum, Thorium, Erbium. SISTER fails because St is not a chemical element symbol.

The relevance of "Russian":

The person who created the modern periodic table, Mendeleev, was a Russian.